Continuous underway measurements of atmospheric and dissolved CO2 were performed on board R/V Aegaeo during the cruise SES_UNLUATA_GR1 that were conducted in the frame of the SESAME-IP project during the period 21/03 - 05/04/2008. The dataset includes Surface underway chemical and physical data collected in the Ionian and Aegean Seas, as well as in the area of Ierapetra AC.  .