RRS Discovery Cruise 306, 23 Jun-06 Jul 2006. Pelagic biogeochemistry of the PAP Site

The aim of this cruise was to develop a better understanding of carbon cycling in the pelagic waters of the Porcupine Abyssal Plain (PAP). There were three objectives 1) Turnaround moorings at the PAP Observatory; 2) Conduct a 1-D time series on the central station of a wide range of biogeochemical processes and to back this up with a mesoscale survey of key variables; 3) To trial the use of Autosub for mesoscale surveys in conjunction with the ship. All objectives were met, although the tops of the moorings were found to be missing probably due to fishing activity and the Autosub trials were incomplete due to vehicle failure. A full mesoscale survey was carried out using the ship and an eleven day time series at the central station was achieved.