Spatial and temporal variation of Chromophoric Dissolved Organic Matter absorption in the Caribbean

Spatial and temporal variation of Chromophoric Dissolved Organic Matter (CDOM) absorption was studied in the course of diverse research cruises through the Caribbean region. CDOM absorption and spectral slopes showed marked seasonal and spatial variability. Temporal trends showed maximum mean surface CDOM absorption and spectral slopes during summer. The spatial analysis showed highest absorption values in the Gulf of Paria. Values remained relatively high along the Orinoco River Plume throughout the Eastern Caribbean. High values were also found along the edges of a cyclonic eddy with entrained Orinoco River Plume waters. Values outside of the plume were found to be low. Differences found on spectral slopes point to spatial-temporal differences in water mass sources in the Caribbean. Mesoscale eddies affect the spatial and temporal distribution of CDOM by advection of the Amazon and Orinoco River plumes into the Eastern Caribbean basin creating complex mosaics of optically clear and optically dense waters.