Global analysis of concurrent decadal changes in the world ocean phytoplankton and their forcing variables (SST, wind, irradiance)

Abstract

A consistent time series of the world ocean chlorophyll concentration was produced from satellite ocean color observations by the CZCS sensor (1979-1983) and the SeaWiFS sensor (1998-2002) (Antoine et al, 2005). This reanalysis showed an overall increase of the world ocean average phytoplankton chlorophyll (Chl) by as much as 20% over two decades. Following this result, a project, called“GLOBPHY, was recently set up to analyse these decadal changes in the global ocean phytoplankton in parallel to their forcing variables. The objective is, therefore, to confront the ocean colour record with those of other parameters which are likely to have played a role in the evolution of the total phytoplankton biomass (temperature, irradiation, wind…). The data are taken from other satellite observations and from re-analyses of the outputs of global weather forecasting models. The analysis allows a first phase of interpretation of the observed changes, by checking their coherence with those observed in the forcing variables of the phytoplanktonic compartment.