%0 Journal Article
%T Large variability in continental shelf production of phytoplankton carbon revealed by satellite
%A B. F. J nsson
%A J. E. Salisbury
%A A. Mahadevan
%J Biogeosciences (BG) & Discussions (BGD)
%D 2011
%I Copernicus Publications
%X We estimate the net production of phytoplankton in the Gulf of Maine (GoM) over a 3-yr period using satellite ocean color data in conjunction with surface velocities from a high-resolution operational ocean circulation model. Chlorophyll (Chl-a) and light attenuation (K490) products are combined with a carbon to chlorophyll model to estimate the phytoplankton carbon (PC) stock in the euphotic layer. A satellite-based productivity, termed NCPe in analogy with net community production (NCP), is derived by tracking changes in satellite-derived PC from one satellite image to the next, along water parcel trajectories calculated with surface velocities from the ocean circulation model. Such an along-trajectory analysis of satellite data discounts the effect of advection that would otherwise contribute to the temporal change between consecutive images viewed in the fixed reference frame. Our results show a high variability of up to ¡À500 mg C m 2 d 1 in NCPe on spatial scales of 10¨C100 km. A region-wide median NCPe of 40¨C50 mg C m 2 d 1 is often prevalent in the Gulf, while blooms attain peak values of 400 mg C m 2 d 1 for a few days. The spatio-temporal variability of NCPe in this region, though conditioned by seasonality, is dominated by events lasting a few days, which if integrated, lead to large inter-annual variability in the annual carbon budget. This study is a step toward achieving synoptic and time-dependent estimates of oceanic productivity and NCP from satellite data.
%U http://www.biogeosciences.net/8/1213/2011/bg-8-1213-2011.html