Surface Mixed Layer Profile of Physical and Biogeochemical Variables in the Subpolar North-West and -East Atlantic Ocean: A Data-Model Comparison Study

Nsikak U. Benson^1*, Francis E. Asuquo², Oladele O. Osibanjo³, Usoro M. Etesin⁴, Adebusayo E. Adedapo¹

¹Environmental Chemistry Unit, Department of Chemistry, Covenant University, Ota, Nigeria.
²Institute of Oceanography, Department of Physical Oceanography, University of Calabar, Calabar, Nigeria.
³Department of Chemistry, University of Ibadan, Ibadan, Nigeria.
⁴Department of Chemistry, AkwaIbom State University, Mkpat-Enin, Nigeria.

DOI: 10.4236/ojms.2015.51004                

Abstract

This paper presents a study of physical and biogeochemical variables using numerical model and mixed layer oceanographic data from a 2 - 3 year in situmeasurements in the Northwestern and Northeastern sites of the Atlantic Ocean. Model outputs are presented and indicated that very good estimates may be obtained. The outputs showed considerable agreement in reproducing seasonal distributions of pCO₂, pCO₂-T, pCO₂-nonT, mixed layer temperature, and chlorophyll-a in both winter and summer, and therefore provide useful physical and theoretical understanding of their biogeochemistry. The model pCO₂indicated a distinct temporal variability with seasonal changes coinciding with the change in sea surface temperature. It also provides an agreement that there is a strong seasonal cycle of mixed layer parameters filliped by nonthermal and physical factors. As an outgrowth of this work, the pCO₂ model outputs affirm the North Atlantic Ocean capacity as an important oceanographic sink for anthropogenic carbon dioxide.

Keywords

Mixed Layer Profile, pCO₂, Ocean Circulation Model, Model Validation, North Atlantic Ocean

Conflicts of Interest

The authors declare no conflicts of interest.

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