This collection of datasets contains data measured by various CTD instruments which have been deployed at the OBSEA platform since May, 2009. OBSEA is a permanent underwater cabled seabed observatory located in front of the Catalan's coast near Barcelona, at 20 m depth which is used as a test site for different experiments related with marine sensors. It has a sea station and a ground station, which include a surface buoy equipped with weather station and camera and a coastal cabled system (seabed platform). OBSEA is part of the European Multidisciplinary Seafloor Observatory (EMSO) infrastructure and participates as a Coastal Observatory data provider and Test Site on the JERICO-RI.For a comfortable handling of these CTD data they were summarized monthly to one data set each. A complete list of the datasets belonging to this collection can be found at the end of this page.