The CO₂ system in the Mediterranean Sea: a basin wide perspective

Abstract

Abstract. This paper provides an extensive vertical and longitudinal description of the CO2 system variables (Total Alkalinity – TA, dissolved inorganic carbon – DIC and pH) along an East-West transect and across the Sardinia–Sicily passage in the Mediterranean Sea (MedSea) from two oceanographic cruises conducted in 2011 measuring CO2 variables in a coordinated fashion, the RV Meteor M84/3 and the RV Urania EuroFleets 11, respectively. The over-determined CO2 system allowed performing the first internal consistency analysis for the particularly warm, high salinity and alkalinity MedSea waters. This basin is considered a "laboratory basin" suffering dramatic changes in its oceanographic and biogeochemical conditions derived from natural and anthropogenic forces. Despite this, little is known about the CO2 system variability in the whole basin. This work aims to be a benchmark for future studies about the CO2 system space-time variability in the MedSea. In this sense we provide full-depth and length CO2 distributions across the MedSea, and property – property plots showing in each sub-basin post-Eastern Mediterranean Transient (EMT) situation with regard to TA, DIC and pH.