By Carol // Wednesday 26 Sep // 20:05:15 // 3 Comments // View
So today was the day that “Arty Bob”, the Cape Farewell ARGO float was to make a brief debut into the world before descending into the depths of the Greenland Sea. Guess we’d better get the science out of the way……the ARGO float is programmed to sink to a specific depth in the ocean. It will then be taken by the current we want to investigate, in this case the East Greenland Current, and track it for approximately 3 years. At 10 day intervals, the float will sink to 2000m, before rising to the surface recording temperature, salinity and density on the way. At the surface it will send all the data and its current position back via satellite to the British Oceanographic Centre in Liverpool. The data can then be accessed by anyone throughout the world via the Met Office website.
We deployed the float at 0 degrees Longtitude, the same meridian that runs through Greenwich, London, and 74 degrees Latitude. By deploying Bob north of the Mohns Ridge, it is hoped that the float will show how the deep Arctic water is channelled past this ridge, either through one of two knick points in the ridge, or by being diverted north-east and around the ridge before resuming its southerly course.
The ARGO crate was opened with great excitement, and the float activated at 13.20 UTC. It then had to be left for at least 30 minutes in order for the oil bladder to fully inflate. This bladder controls the ascents and descents that the float will undertake in the course of its life, and so early deployment could have meant a very untimely end to Bob!
We head into the wind and drop our sailing speed. Everyone is watching from the side of the boat – or in Nick’s case harnessed in but hanging off the outside of the boat with his camera – as Bob, merrily beeping away to let the satellite receiving station know that he is active, is carefully lowered into the water at 14.36 UTC. The float slowly rights itself, proving to be as much of a draw for a flock of seagulls as for all aboard the Nooderlicht. It has to be said that this is a first in my scientific career – to merrily launch £25k of equipment over the side of a boat and not be expected to retrieve it! Bob will stay at the surface for a few hours, ensuring that all messages are being received clearly, before being instructed to sink to the pre-programmed “cruising” depth of 1500m. Then let the journey into the deep ocean begin………. check back with us in a week or so when we have the ID number and we can all follow Bob’s great ocean adventure.
Cape Farewell’s Arty Bob joins the ranks of almost 3000 ARGO floats that have been deployed throughout the world by 20 different countries. However, only Bob has been signed by comedian Marcus Brigstocke, with an added joke for the marine world inscribed on its side. Marcus has promised free tickets for his next show to anyone who gets the joke (literally!!) Maybe it was the lure of this that had a northern bottle-nosed whale heading in Bob’s direction as we sailed off towards ScoresbySund.
So where is Arty Bob now?
Click to find out where Arty Bob is and to see what he’s been up to.
(Arty Bob’s ID: 6900609)