Articles | Volume 9, issue 2
Ocean Sci., 9, 301–324, 2013
Ocean Sci., 9, 301–324, 2013

Research article 19 Mar 2013

Research article | 19 Mar 2013

Long-term monitoring programme of the hydrological variability in the Mediterranean Sea: a first overview of the HYDROCHANGES network

K. Schroeder1,*, C. Millot2, L. Bengara3, S. Ben Ismail4, M. Bensi5, M. Borghini1, G. Budillon6, V. Cardin5, L. Coppola7,8, C. Curtil9, A. Drago10, B. El Moumni3, J. Font11, J. L. Fuda2, J. García-Lafuente12, G. P. Gasparini1, H. Kontoyiannis13, D. Lefevre2, P. Puig11, P. Raimbault2, G. Rougier2, J. Salat11, C. Sammari4, J. C. Sánchez Garrido12, A. Sanchez-Roman12, S. Sparnocchia14, C. Tamburini2, I. Taupier-Letage2, A. Theocharis13, M. Vargas-Yáñez15, and A. Vetrano1 K. Schroeder et al.
  • 1CNR-ISMAR, Forte Santa Teresa, 19036 Pozzuolo di Lerici, La Spezia, Italy
  • 2Aix-Marseille Univ., Mediterranean Institute of Oceanography (MIO), 13288 Marseille cedex 09, France; Université du Sud Toulon-Var, 83957 La Garde cedex, France; CNRS/INSU, MIO ,UMR 7294, 13288 Marseille cedex 09, France; IRD, MIO, UR235, 13288 Marseille
  • 3Université Abdelmalek ESSAADI, FP – Larache, Morocco
  • 4Institut National des Sciences et Technologies de la Mer (INSTM), 28 rue 2 mars 1934 Salammbo, 2025, Tunisia
  • 5Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, Borgo Grotta Gigante, 42/c, 34010, Sgonico (Trieste), Italy
  • 6Università degli Studi di Napoli "Parthenope", Dipartimento di Scienze per l'Ambiente, 80143 Napoli, Italy
  • 7Université Pierre et Marie Curie (UPMC), UMS829, Observatoire Océanologique de Villefranche-sur-Mer, 06234 Villefranche-sur-Mer, France
  • 8CNRS/INSU, UMS829, Observatoire Océanologique de Villefranche-sur-Mer, 06234 Villefranche-sur-Mer, France
  • 9CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France
  • 10Physical Oceanography Unit, IOI-Malta Operational Centre, University of Malta, Msida MSD08, Malta
  • 11Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta, 37–49, 08003, Barcelona, Spain
  • 12Physical Oceanography Group, University of Málaga, Málaga, Spain
  • 13Hellenic Centre for Marine Research, 46.7 km Athens-Sounio Avenue, 19013, Anavyssos, Greece
  • 14CNR-ISMAR, Viale Romolo Gessi 2, 34123 Trieste, Italy
  • 15Instituto Español de Oceanografía, Centro Oceanográfico de Málaga, Puerto pesquero s/n, 29640, Fuengirola, Málaga, Spain
  • *now at: CNR-ISMAR, Arsenale – Tesa 104, Castello 2737/F, 30122 Venezia, Italy

Abstract. The long-term monitoring of basic hydrological parameters (temperature and salinity), collected as time series with adequate temporal resolution (i.e. with a sampling interval allowing the resolution of all important timescales) in key places of the Mediterranean Sea (straits and channels, zones of dense water formation, deep parts of the basins), constitute a priority in the context of global changes. This led CIESM (The Mediterranean Science Commission) to support, since 2002, the HYDROCHANGES programme (http//, a network of autonomous conductivity, temperature, and depth (CTD) sensors, deployed on mainly short and easily manageable subsurface moorings, within the core of a certain water mass. The HYDROCHANGES strategy is twofold and develops on different scales. To get information about long-term changes of hydrological characteristics, long time series are needed. But before these series are long enough they allow the detection of links between them at shorter timescales that may provide extremely valuable information about the functioning of the Mediterranean Sea. The aim of this paper is to present the history of the programme and the current set-up of the network (monitored sites, involved groups) as well as to provide for the first time an overview of all the time series collected under the HYDROCHANGES umbrella, discussing the results obtained thanks to the programme.