<p>Time series of phytoplankton abundance collected with a monthly frequency at 0.5, 5, 10 and 15 meters in the Gulf of Trieste. The time series station C1, located in the Gulf of Trieste in the northernmost part of the Adriatic Sea, is part of the Adriatic Long Term Ecological Research (LTER) site. It is a shallow coastal station (17 m depth) located at 0.2 Km from the coast, at the outer border of the Natural Marine Reserve of Miramare, Trieste. More information about activities carried out and about datasets from other periods can be found at: http://nettuno.ogs.trieste.it/ilter/GoTTs/en_index.html.</p>;