Anthropogenic carbon in the eastern South Pacific Ocean

L. Azouzi (1) , R. Gonçalves Ito (2) , Franck Touratier (1) , Catherine Goyet (1)

1 BDSI - Laboratoire de Biophysique et Dynamique des Systèmes Intégrés
2 Instituto Oceanográfico

We present results from the BIOSOPE cruise in the eastern South Pacific Ocean. In particular, we present estimates of the anthropogenic carbon C_ant^TrOCA distribution in this area using the TrOCA method recently developed by Touratier and Goyet (2004a, b) and Touratier et al. (2007). We study the distribution of this anthropogenic carbon taking into account of the hydrodynamic characteristics of this region. We then compare these results with earlier estimates in nearby areas of the anthropogenic carbon as well as other anthropogenic tracer (CFC-11). The highest concentrations of C_ant^TrOCA are located around 13° S 132° W and 32° S 91° W, and their concentrations are larger than 80 µmol kg^-1 and 70 µmol kg^-1, respectively. The lowest concentrations were observed below 800 m depths (=2 µ mol kg^-1) and at the Oxygen Minimum Zones (OMZ), mainly around 140° W (<11 µmol kg^-1). The comparison with earlier work in nearby areas provides a general trend and indicates that the results presented here are in general agreement with previous knowledge. This work further improves our understanding on the penetration of anthropogenic carbon in the eastern Pacific Ocean.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Astrophysique [astro-ph]; Interfaces continentales, environnement; Océan, Atmosphère; Sciences de la Terre

L. Azouzi, R. Gonçalves Ito, Franck Touratier, Catherine Goyet. Anthropogenic carbon in the eastern South Pacific Ocean. Biogeosciences Discussions, 2007, 4 (3), pp.1815-1837. ⟨hal-00330244⟩