Presenter/Author Information

Barbara J. Robson
Nagur Cherukuru
Vittorio Brando

Keywords

dynamic simulation model, environmental flow, shear stress, benthic plants, nutrient transfer, boundary layer transfers, primary production

Start Date

1-7-2010 12:00 AM

Description

Satellite images provide a rich data source for environmental modelling. Use ofsatellite data for calibration or validation of ocean models is now common-place. Satelliteobservations can also be used more directly to improve model performance - usuallythrough "nudging" of model results towards observed values. We describe a novel approachto satellite data assimilation, applying empirically derived "correction factors" to simulatedoptical conditions in a process-based, three-dimensional biogeochemical model of a coastalsystem. The correction factors (which are functions of simulated salinity and suspendedsolids concentrations) are applied to simulated attenuation and backscattering. The result isimproved simulation of optical conditions and a consequent improvement in simulatedchlorophyll biomass. This approach has two advantages over traditional nudging: 1) themodel retains conservation of mass; 2) the correction factor can be applied beyond thebounds of the satellite observations (e.g. beneath the surface) and can be applied in scenarioruns as well as simulations of current or historical conditions. This work also demonstratesthe benefits of matching what is modelled to what is observed (in this case, attenuation andbackscattering rather than derived optical products).

Share

COinS
 
Jul 1st, 12:00 AM

Using satellite-derived optical data to improve simulation of the 3D light field in a biogeochemical model

Satellite images provide a rich data source for environmental modelling. Use ofsatellite data for calibration or validation of ocean models is now common-place. Satelliteobservations can also be used more directly to improve model performance - usuallythrough "nudging" of model results towards observed values. We describe a novel approachto satellite data assimilation, applying empirically derived "correction factors" to simulatedoptical conditions in a process-based, three-dimensional biogeochemical model of a coastalsystem. The correction factors (which are functions of simulated salinity and suspendedsolids concentrations) are applied to simulated attenuation and backscattering. The result isimproved simulation of optical conditions and a consequent improvement in simulatedchlorophyll biomass. This approach has two advantages over traditional nudging: 1) themodel retains conservation of mass; 2) the correction factor can be applied beyond thebounds of the satellite observations (e.g. beneath the surface) and can be applied in scenarioruns as well as simulations of current or historical conditions. This work also demonstratesthe benefits of matching what is modelled to what is observed (in this case, attenuation andbackscattering rather than derived optical products).