Journal cover Journal topic
Ocean Science An interactive open-access journal of the European Geosciences Union
© Author(s) 2009. This work is distributed under
the Creative Commons Attribution 3.0 License.
29 Oct 2009
Review status
This discussion paper is a preprint. A revision of the manuscript for further review has not been submitted.
Modal composition of the central water in the North Atlantic subtropical gyre
A. Cianca1, R. Santana1, J. P. Marrero1, M. J. Rueda1, and O. Llinás2 1Instituto Canario de Ciencias Marinas (ICCM), Gobierno de Canarias, Apartado 56, Telde, 35200, Spain
2Plataforma Oceánica de Canarias, Carretera de Taliarte n/n, Telde, 35200, Spain
Abstract. The modal composition of the Central Water in the North Atlantic subtropical gyre is not clearly defined, as there are some uncertainties related to mode identification, as well as modes which are not well documented. This study shows that eastern North Atlantic Central Water (eastern NACW) in the subtropical gyre is composed of three modes: The North Atlantic Subpolar Mode Water (NASPMW σt=27.1 to 27.3), the Madeira Mode Water (MMW σt=26.4 to 26.6), and the mode water with a σt near 27.0, which is currently not well documented. We confirmed this mode based on the similarities found between it and the mode waters already reported. The similarities were determined from comparative analyses of the temperature/salinity standard curves and the gradients of the potential density anomalies of two concurrent data sets from two subtropical time-series stations (Bermuda Atlantic Time-series Study, BATS, in the west, and European Station for Time-series in the Ocean Canary Islands, ESTOC, in the east). In order to establish the outcropping regions, the corresponding pycnostads were determined using another climatologic data set (World Ocean Database, WOD2005). In this case, the pycnostads were located based on the presence of standard deviation minima from the average density anomalies. Finally, we confirmed that the pycnostads corresponded to the temperature values related to the modes by overlaying the characteristic modal isotherm of each of the modes in the geographic distribution of the pycnostads. Sea surface temperature data (SST) from the Ocean Pathfinder Program (OPP) were used to estimate the isotherms. The results showed a clear correspondence between the modal isotherms and the pycnostads, for both the modes that have already been documented and the mode confirmed in this study.

Citation: Cianca, A., Santana, R., Marrero, J. P., Rueda, M. J., and Llinás, O.: Modal composition of the central water in the North Atlantic subtropical gyre, Ocean Sci. Discuss.,, in review, 2009.
A. Cianca et al.
A. Cianca et al.


Total article views: 844 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
320 472 52 844 31 39

Views and downloads (calculated since 01 Feb 2013)

Cumulative views and downloads (calculated since 01 Feb 2013)



Latest update: 19 Nov 2017
Publications Copernicus