| The South West Tropical Pacific (SWTP) is generally considered as an N-limiting oligotrophic area with parts characterized by permanent deep thermocline and nutricline as the Melanesian Archipelago. However, ocean color imagery shows in this region a strong seasonal chlorophyll cycle, with large blooms which have for long been attributed to nitrogen-fixing cyanobacteria as Trichodesmium. SeaWiFS surface chlorophyll analysis of the area between 5°S-25°S, 150°E-170°W has been conducted from 1997 to 2004. A strong seasonal and interannual variability is described, which relates well with the sea-truth measured chlorophyll concentrations. An empirical orthogonal function analysis helped in determining principal explicative factors of this variability, and in... |
