Modelling the impact of a La Niña event on a South West Pacific Lagoon

► Impact of freshwater inputs induced by heavy rainfall of the 2008 La Niña event. ► Development of 3D coupled on-line hydrodynamic-biogeochemical model (New Caledonia). ► Coupling strategy improvement through biogeochemical feedback on heat fluxes calculus. ► New insights into chlorophyll plumes transport from east coast to south west lagoon. ► Surface transport depends on winds/tide-induced current and oceanic current balance.