A Lagrangian ensemble model of Calanus finmarchicus coupled with a 1-D ecosystem model

A population dynamics model of Calanus finmarchicus based on Lagrangian par ticles has been coupled with a 1-D ecosystem model. Each of the particles r epresents a variable number of copepods which experience the same fate. The refore all copepods of a single particle represent a cohort and are charact erized by a common set of individual properties such as age, development-st age, depth, structural weight (length), lipid pool or food satiation. The p hysical environment is parameterized by a 1-D-water column with a vertical resolution of 1 m and a maximum depth of 800 m. Copepod food supply is prov ided by an interactive Eulerian NPZD model where Z represents microzooplank ton. The model correctly reproduces both the dynamics of the ecosystem and the life history of the copepods in the Norwegian Sea. Simulated results of trajectories of particles in the water column, and of individual growth an d stage development were analysed. Results on seasonal abundance, developme nt time, number of generations, depth profiles, and patterns of diurnal and ontogenic migration are compared with field data from OWS India.