Open AccessSeasonal variation in total organic carbon in the northeast Atlantic in 2000–2001
Author(s) -
Sohrin Rumi,
Sempéré Richard
Publication year - 2005
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2004jc002731
Subject(s) - total organic carbon , oceanography , environmental science , spring bloom , flux (metallurgy) , thermocline , seasonality , phytoplankton , mixed layer , chlorophyll a , surface water , latitude , surface layer , middle latitudes , organic matter , atmospheric sciences , geology , nutrient , environmental chemistry , chemistry , biochemistry , statistics , mathematics , organic chemistry , geodesy , layer (electronics) , environmental engineering
Total organic carbon (TOC) was measured in the midlatitudes of the northeast Atlantic in 2000–2001 during the Programme Océan Multidisciplinaire Méso Echelle (POMME). In spring, mixed layer depth (MLD) was positively correlated with the north latitude, while the surface TOC and chlorophyll‐ a (Chl a ) were negatively correlated with it. It indicates the northward propagation of TOC accumulation along the onset of spring bloom, which was triggered by shoaling of MLD from the south. Surface TOC was highest in summer, though surface Chl a was lowest. Surface TOC was significantly correlated with surface Chl a during winter and spring but not during summer or fall, indicating the minor influence of total phytoplankton biomass on surface TOC distribution in the oligotrophic season. High surface TOC in summer and fall was related with shallow MLD, which could hold fresh TOC near the surface. Downward TOC flux from the surface to below the seasonal thermocline was estimated for the processes of winter convection ( F c ), turbulent diffusion ( F d ) and sinking flux ( F p ). The sum of these fluxes accounts for 6–75% of annual new production. To our knowledge, this is the first estimation based on the simultaneous measurement of F c , F d , F p , and annual new production.