A repeat seasonal hydrographic survey of the Balearic Sea, monitoring the Ibiza and Mallorca Channels. 21 CTD stations were carried out over 4 days; the stations forming one transect across the Ibiza Channel (IC) and one transect across the Mallorca Channel (MC). 2 surface drifters SVP and 2 ARVOR 2 were also deployed in the Ibiza Channel.