14 June - Four moorings up!

Today we successfully recovered the fourth of the moorings we had left behind on the seabed nearly two years ago to collect a time series of the biological particles, mainly microscopic plants and animals , that rain down from the sunlit surface ocean to the floor of the Iceland basin some one and three quarter miles below us.  Acting like giant funnels, the sediment traps on these moorings, collecting this particulate material, support our quest to discover how efficiently the microscopic plants of the surface ocean lock up carbon dioxide, through photosynthesis, and the cycle of life and death transports this carbon to the ocean sediments.  These moorings were designed to be recovered last year, but a combination of ship mechanical problems and fairly typical poor weather at these latitudes of the N. Atlantic scuttled all chances of recovery during 2008.

As scientists, our sincere thanks goes to all the crew, technicians, and officers of RRS Discovery; yesterday we witnessed a record breaking recovery time of three of the moorings in just 15 hours including a steaming distance of around 140 km.  This really was a great job done well.  That left just one to complete this morning, naturally this would be the only sulky one, as it refused to communicate with us despite ‘shouting’ at it with the required coded acoustic messages for over 50 minutes.  However, although mute it was obedient, and 50 minutes after we had sent the instruction to let go of the seabed, it’s buoyancy floats made a welcome appearance on the surface much to everyone’s relief.  Once back at the lab in a few weeks time, the material caught in the traps will be examined under microscopes and all manner of complex chemical processes will tease out the details of it’s composition.  Students will extract everything there is to be learnt from these data about the processes that control the natural biogeochemical cycles of this part of the ocean and expand our understanding of the blue planet a little bit further.