Gibraltar monitoring - CIESM Hydrochanges Programme
28 October 2005, CIESM News

The maintenance of the two CTDs set on short moorings in the strait of Gibraltar (at depths of 80m and 270 m respectively) for monitoring the Atlantic inflow and the Mediterranean outflow was performed from 10-12 October onboard EL LAHICQ, a hydrographic vessel from the Moroccan Hydrographic Service (SHOMAR).

With the help of favourable weather conditions and thanks to the remarquable efficiency of captain Britel and his crew, both moorings were acoustically released and recovered in a few hours on the first day. A full day of hard work was then necessary for reconditioning them in Tangiers' harbour. A considerable effort was particularly requested for cleaning and reconditioning the 80m-mooring instruments and subsurface floatation, heavily colonized by huge barnacles.

On October 12, two newly calibrated SBE37 CTDs were deployed in place of the ones just recovered, once more in very propitious sea conditions. The temperature and salinity time series collected by Hydrochanges in the strait of Gibraltar - a key place if any - are the longest ever recorded (almost 3 years now of uninterrupted hourly data since January 2003 !) and the deepest ones, from 270m, have already revealed dramatic changes of the Mediterranean outflow composition compared to the data obtained from dedicated experiments conducted in the mid-1980s. An analysis of these exciting results will be soon available on the CIESM website and, in more detail, in the scientific literature.

To be continued !

Jean-Luc Fuda
Joint co-ordinator, Hydrochanges Program