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.
- Balopoulos E, Theocharis A, Kontoyiannis H, Varnavas S, Voutsinou-Taliadouri F, Iona A, Souvermezoglou A, Ignatiades L, Gotsis-Skretas O, Pavlidou A (1999) Major advances in the oceanography of the southern Aegean Sea–Cretan Straits system (eastern Mediterranean). Prog Oceanogr 44:109–130CrossRefGoogle Scholar
- Georgopoulos D, Theocharis A, Zodiatis G (1989) Intermediate water formation in the Cretan Sea (S. Aegean Sea). Oceanol Acta 12(4):353–359Google Scholar
- Kassis D, Hatzikosti E, Nittis K, Perivoliotis L, Tzimeas K (2008) POSEIDON data management and quality control. Marine data and information systems, IMDIS 2008, March 31-April 2 2008. Book of Abstracts, Athens, p 161Google Scholar
- Kassis D, Ballas D, Nittis K, Pagonis P, Georgopoulos D (2009) An integrated ocean observing system in the Ionian Sea. In: 3rd international conference on underwater acoustic measurements: technologies and results, Nafplion, 21-26 June 2009, Book of Abstracts., p 144Google Scholar
- Kassis D, Nittis K (2010) Aegean Sea surface circulation dynamics derived from real-time buoy measurements. In: Proceedings of the 5th international conference of EuroGOOS, EuroGOOS publication n. 28, ISBN 978-91-974828-6-8., pp 142–147Google Scholar
- Kassis D, Nittis K, Perivoliotis L, Chondronasios A, Petihakis G, Pagonis P. 2011. Hydrodynamic properties of the south Ionian Sea based on the POSEIDON Pylos observatory. Proceedings of the 6th international conference on EuroGOOS. eds. H. Dahlin, N. C. Flemming and S. Petersson. EuroGOOS Publication. pp.59-66 ISBN 978-91-974828.Google Scholar
- Korres G, Nittis K, Perivoliotis L, Tsiaras K, Papadopoulos A, Triantafyllou G, Hoteit I (2010) Forecasting the Aegean Sea hydrodynamics within the POSEIDON-II operational system. J Operat Oceanogr 3(1):37–49 (13) Google Scholar
- Krokos G, Velaoras D, Korres G, Perivoliotis L, Theocharis A. 2013. On the continuous functioning of an internal mechanism that drives the Eastern Mediterranean thermohaline circulation: the recent activation of the Aegean Sea as a dense water source area. J Marine Syst. 129; 2014, Pages 484-489, ISSN 0924-7963, http://dx.doi.org/ 10.1016/j.jmarsys.2013.10.002.
- Malanotte-Rizzoli P, Manca B, Rivera D’ Alcala M, Theocharis A, Bergamasco A, Bregant D, Budillon G, Civitarese G, Georgopoulos D, Michelato A, Sansone E, Scarazzato P, Souverrmezoglou E (1997) A synthesis of the Ionian hydrography, circulation and water mass pathways during POEM—Phase I. Prog Oceanogr 39:153–204CrossRefGoogle Scholar
- Nittis K, Perivoliotis L, Korres G, Ballas D, Papadopoulos A, Triantafyllou G, Pagonis P, Tsiaras K, Mallios A, Drakopoulos P (2008) POSEIDON II: upgrading the monitoring and forecasting services in the Eastern Mediterranean Sea. Abstracts book of the 5th EuroGOOS conference, 20-22 May 2008 Exeter UK., p 61Google Scholar
- Petihakis G, Nittis K, Ballas D, Kassis D, Pagonis P, Perivoliotis L et al. 2010. The POSEIDON reference time-series stations of the Eastern Mediterranean Sea, in proceedings of the, Hall J, Harrison DE., Stammer D, Eds., ESA Publication WPP-306.Google Scholar
- Petihakis G, Ntoumas M, Kassis D, Potiris M, Ballas D, Chondronassios A et al. 2011. Activities of the calibration laboratory at HCMR-Crete – progress and challenges. In proccedings of the 6th International Conference on EuroGOOS, pp.15-22 eds. H. Dahlin, N. C. Flemming and S. Petersson. EuroGOOS Publication no. ISBN 978-91-974828Google Scholar
- Pollak MI (1951) The sources of deep water in the eastern Mediterranean Sea. J Mar Res 10:128–152Google Scholar
- Poulain P-M, Ursella L, Barbanti R (2004) Assessment of APEX float tests in the Catalan Sea, OGS technical report, 23-2004-OGA-5. OGS, Trieste, p 27Google Scholar
- Pouliquen S, Carval T, Loubrieu T, von Schuckmann K, Wehde HL, SjurRingheim L, Hammarklint T, Harman A, Soetje K, Gies T, de Alfonso M, Perivoliotis L, Kassis D, Marinova D (2012) Real time in situ data management system for EuroGOOS: a ROOSes-MyOcean joint effort. In proccedings of EGU general assembly, Vienna, Austria 22 – 27 April 2012. Geophys Res Abstr 14:EGU2012–10061Google Scholar
- Rupolo W. 2003. Task 4120: Intermediate currents. MFSTEP deliverable WP4D2. (http://poseidon.ogs.trieste.it/WP4/pdf/TASK4120.pdf).
- Schroeder K, Millot C, Bengara L, Ben Ismail S, Bensi M, Borghini M, Budillon G, Cardin V, Coppola L, Curtil C, Drago A, El Moumni B, Font J, Fuda JL, García-Lafuente J, Gasparini GP, Kontoyiannis H, Lefevre D, Puig P, Raimbault P, Rougier G, Salat J, Sammari C, Sánchez Garrido JC, Sanchez-Roman A, Sparnocchia S, Tamburini C, Taupier-Letage I, Theocharis A, Vargas-Yáñez M, Vetrano A (2013) Long-term monitoring programme of the hydrological variability in the Mediterranean Sea: a first overview of the HYDROCHANGES network. Ocean Sci 9:301–324. doi: 10.5194/os-9-301-2013 CrossRefGoogle Scholar
- Theocharis A, Georgopoulos D, Zodiatis G (1988) Late winter hydrological characteristics and circulation of the Cretan Sea (S. Aegean), EGS XIII general assembly, Bologna, Italy, March, 1988, Annales Geophysicae, Special Issue, 70Google Scholar
- Zervakis V, Nittis K, Perivoliotis L, Tziavos C (2002) A comparison of model predictions to observations of seasonal variability and circulation in the Eastern Mediterranean. Global Atmosph Ocean Sys 8(2–3):141–162Google Scholar
- Zodiatis G (1991) The hydrological conditions and the circulation in the Cretan Sea during late summer 1987. Annales Geophysicae 9:233–238Google Scholar
- Zodiatis G (1994) Advection of Black Sea water in the north Aegean Sea, global atmos. Ocean Syst 2(1):41–60Google Scholar