Seasonal and Interannual Variability of the CO2 System in the Eastern Mediterranean Sea: A Case Study in the North Western Levantine Basin

The seasonal variability of the carbonate system in eastern Mediterranean Sea (EMed) was investigated based on discrete total alkalinity (A T ), dissolved inorganic carbon (C and pH measurements collected during three cruises around Crete between June 2018 March 2019. This study presents a detailed description this new chemistry dataset Sea. We show that North Western Levantine Basin (NWLB) is unique terms range A variation vs. C upper water column over an annual cycle. reasons for singularity NWLB can be explained by interplay strong evaporation concomitant consumption autotrophic processes. high variations, combined to temperature changes, has impact seawater p CO 2 ( S W ). Based Argo float data, entire cycle been reconstructed order estimate temporal sequence potential “source” “sink” atmospheric . By combining with previous observations NWLB, shows significant ocean acidification decrease oceanic surface 25 ?0.0024 ± 0.0004 units.a –1 changes are driven increase but also unexplained content. If we consider EMed will, future, encounter longer, more intense warmer summer seasons, proposes some perspectives functioning “future” EMed.