Ocean color response to an episode of heavy rainfall in the lagoon of New Caledonia

Cécile Dupouy, Robert Frouin, Rüdiger Röttgers, Jacques Neveux, Francis Gallois, Jean-Yves Panché, Philippe Gerard, Clément Fontana, Christel Pinazo, Sylvain Ouillon, Audrey Minghelli-Roman, Robert J. Frouin
2009 Ocean Remote Sensing: Methods and Applications  
Inherent optical properties (IOPs) and remote sensing reflectance were measured in the southern part of the lagoon of New Caledonia during the VALHYBIO cruise (March-April 2008). The goal was to validate satellite chlorophyll data from MODIS and MERIS and to validate simulations of surface chlorophyll by a biogeochemical model. Physical parameters were collected from a Seabird CTD. Particulate and detritus absorption were measured with the filter pad technique. Backscattering was measured with
more » ... Hydroscat-6. Mapping of IOPs and Rrs were done for the whole southern lagoon area and compared with pigment maps. The cruise provided a description of the IOPs in different water types including bays, open ocean waters, mid-shelf lagoon, and above reefs. With respect to climatology, the heavy rainfall episode of March-April 2008 resulted in a large increase in chlorophyll-a concentration (by a factor of 3) attributed to increased nutrient availability from land drainage. Low backscattering ratios characterized the chlorophyll-rich plumes associated with the nutrient increase. The data are useful for the development of a specific algorithm for chlorophyll concentration retrieval by satellite in all oligotrophic lagoons during dry and wet seasons.
doi:10.1117/12.829251 fatcat:7a2b3gypjnbqxppfieddze4mta