Hydrodynamic variability of the Cretan Sea derived from Argo float profiles and multi-parametric buoy measurements during 2010–2012
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In this work, we examine the complex hydrology of the Cretan Sea, an important area which affects the dynamics of the Eastern Mediterranean basin. We use T/S profile data derived from the first Argo float deployed in the area during June 2010 within the framework of the Greek Argo program. Temperature and salinity profiles were measured over a 2-year period, analyzed, and combined with time series data recorded from the POSEIDON E1-M3A multi-parametric instrumentation platform operating in the area since 2007. The acquired datasets have been enriched with available CTD profiles taken on the mooring site during cruise maintenance surveys. The combined research activities resulted in a large dataset of physical properties allowing extended geographical coverage and an in-depth analysis of the Cretan Sea dynamics during this 2-year period. Data analysis shows significant variability of water masses of different origin at subsurface and deep layers. This confirms previous findings describing the area as transitional with water masses of different origin meeting and interacting. Furthermore, additional features of the area are described combining information from satellite altimetry. In this study, new circulation systems are identified at intermediate and subsurface layers affecting both the dynamic behavior of the basin’s upper thermocline and the intermediate/deep water mass tempo-spatial variability. We further investigate the physical properties of the water column and suggest an updated mesoscale circulation picture based on the dynamics of the variable hydrological regimes of the Cretan Sea basin.
KeywordsArgo float Greek Argo POSEIDON E1-M3A Cretan Sea hydrology
This work has been supported by the Greek Argo project funded by the National Strategic Reference Framework (NSRF) 2007–2013.
The POSEIDON I and II projects were funded by the Financial Mechanism of the European Economic Area and the Hellenic Program of Public Investments. The satellite products were supplied by the CLS Space Oceanography Division, Toulouse, France.
We would also like to thank the GIS and Remote Sensing Lab of HCMR–Institute of oceanography and all the people of the POSEIDON team (technicians and scientists) who contributed to this effort.
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