South Rockall Trough Sub-surface Mooring Deployment from April 2020 - June 2021

Deployment of a sub-surface mooring at South Rockall (52° 59.956' N, -16° 28.84' W) from the RV Celtic Explorer survey CE20001 on 26/04/2020. Recovered on 02/06/2021 by the RV Celtic Explorer survey CE21014. Upon recovery, it was apparent that the top float with a Teledyne ADCP and a CTD were missing and pressumed lost. On interrogation of the CTD data from the remaining part of the mooring, it became clear that the mooring was split on March 16th 2021. However, in Decmeber 2021, colleagues at the Scottish Association for Marine Science (SAMS) notified the Marine Institute that they had recovered the float along with the ADCP and attached CTD after it had washed up on a beach on the Isle of Tiree off the west coast of Scotland on December 4th 2021. The sensors were sent back to the Marine Institute for a successful recovery. The purpose of this activity is to collect data to help understand the variability in the water column not visible at the surface and provide context to CTD profile data collected in the South Rockall Trough. These data are vital in understanding the likely impact of future ocean climate scenarios on key marine sectors as well as understanding possible impacts on ecosystem in the North East Atlantic Ocean.