Spatial and temporal coherence between Amazon River discharge, salinity, and light absorption by colored organic carbon in western tropical Atlantic surface waters

Type Article
Date 2011-07
Language English
Author(s) Salisbury J.1, Vandemark D.1, Campbell J.1, Hunt C.1, Wisser D.2, Reul NicolasORCID3, Chapron Bertrand3
Affiliation(s) 1 : Univ New Hampshire, Ocean Proc Anal Lab, Durham, NH 03824 USA
2 : Univ New Hampshire, Water Syst Anal Grp, Durham, NH 03824 USA
3 : Inst Francais Rech Exploitat Mer, Lab Oceanog Spatiale, Ctr Brest, F-29280 Plouzane, France
Source Journal Of Geophysical Research-oceans (0148-0227) (Amer Geophysical Union), 2011-07 , Vol. 116 , N. C00H02 , P. 14 p.
DOI 10.1029/2011JC006989
WOS© Times Cited 42
Abstract The temporal evolution and spatial distribution of surface salinity and colored detrital matter (cdm) were evaluated within and adjacent to the Amazon River Plume. Study objectives were as follows: first, to document the spatial coherence between Amazon discharge, salinity, cdm, and the nature of the salinity-cdm relationship; second, to document the temporal and spatial variability of cdm along the trajectory of the low-salinity Amazon Plume, and third, to explore the departure of cdm from conservative mixing behavior along the plume trajectory into the open ocean. Time series (2003-2007) of surface salinity estimated using the Advanced Microwave Scanning Radiometer-Earth Observing System and corresponding satellite cdm absorption (acdm) data documented a plume of freshened, colored water emanating from the Amazon. Salinity and acdm were generally coherent, but there were regions in which spatial patterns of salinity and acdm did not coincide. Salinity was oppositely phased with discharge, whereas acdm was in phase but lagged discharge and typically remained high after maximum discharge. Along the river plume trajectory, acdm was inversely correlated with salinity, yet there was considerable deviation from conservative mixing behavior during all seasons. Positive anomalies in a linear relationship between salinity and acdm corresponded to areas of enhanced satellite-retrieved net primary productivity, suggesting the importance of phytoplankton biomass or its subsequent remineralization as a source of cdm. Negative anomalies tended to predominate at the distal sections of the plume trajectories, an observation consistent with the process of photo-oxidation of cdm over observed time scales of days to weeks.
Full Text
File Pages Size Access
Publisher's official version 14 1 MB Open access
Top of the page

How to cite 

Salisbury J., Vandemark D., Campbell J., Hunt C., Wisser D., Reul Nicolas, Chapron Bertrand (2011). Spatial and temporal coherence between Amazon River discharge, salinity, and light absorption by colored organic carbon in western tropical Atlantic surface waters. Journal Of Geophysical Research-oceans, 116(C00H02), 14 p. Publisher's official version : https://doi.org/10.1029/2011JC006989 , Open Access version : https://archimer.ifremer.fr/doc/00041/15218/