Seasonal and inter-annual variability of particulate organic matter in the global ocean

Abstract

The geographic distribution and seasonal to inter-annual variability of the particulate backscattering coefficient, bbp, is described and compared with that of chlorophyll concentration, Chl. Both variables are obtained from satellite-derived ocean color and inverse modeling. In general, bbp exhibits larger seasonal variations than Chl, and the bbp values are more evenly distributed in space, especially at low and middle latitudes. A phase shift between the annual cycles of bbp and Chl is evidenced, and is attributed to the presence of an important pool of non-pigmented particles. Converting bbp to particulate organic carbon, POC, the annual mean surface POC pool between 60°S and 60°N is about 19 Tg C per meter.