%0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Fuchs, R. %A Dupouy, Cécile %A Douillet, Pascal %A Caillaud, M. %A Mangin, A. %A Pinazo, C. %T Modelling the impact of a La Nina event on a South West Pacific Lagoon %D 2012 %L fdi:010057125 %G ENG %J Marine Pollution Bulletin %@ 0025-326X %K 3D coupled model ; Biogeochemistry ; Hydrodynamics ; Coral reef lagoon ; La Nina ; Freshwater inputs %M ISI:000307492800023 %N 8 %P 1596-1613 %R 10.1016/j.marpolbul.2012.05.016 %U https://www.documentation.ird.fr/hor/fdi:010057125 %> https://www.documentation.ird.fr/intranet/publi/2012/09/010057125.pdf %V 64 %W Horizon (IRD) %X In view of increasing environmental awareness and biodiversity conservation, understanding the main forcing mechanism driving biogeochemical cycles in coral reefs and lagoon coastal areas is a priority. La Nina events cause unbalanced situations in the Equatorial Pacific and result in enhanced precipitation in South West Pacific coastal areas. We investigated the impact of heavy rainfalls during the 2008 La Nina event on the New Caledonia lagoon using a 3D coupled on-line hydrodynamic-biogeochemical model. Simulations and data showed that the whole lagoon was impacted by river inputs and stronger hydrodynamics, enhancing chlorophyll-a concentration by a factor between 1.7 and 1.9. The coupled model provided new insights into plume transport, highlighting that eastern plumes can be advected northwards or can reach the South West Lagoon, depending on the balance between regional, tide-induced, and wind-induced surface currents. It also provided a synoptic view of lagoon biogeochemical-hydrodynamic response, when remote sensing data are not available due to cloud coverage. %$ 032 ; 038 ; 020