Disko-very Bob the ARGO float

Tags: Emily Venables, Simon Boxall

Simon Boxall and Emily Venables launch the ARGO float

BBC's Quentin Cooper at the launch the ARGO float

“Disko-very Bob” has made it into the West Greenland Current with everything running smoothly – at last! The water column sampling didn’t start well last week (hence lack of my blog) with the failure of the CTD, designed to measure profiles of temperature and salinity to 200m. However what we did see in a test run was that the waters in this part of the ocean show strong inputs of fresh water from the melting glaciers that border the coast.

A few days ago we used our back up device – only capable of measuring to 10m depth – to observe at close quarters the melt water coming off the glacier in Perdlerfiup Kangerdlua. There was little evidence of liquid water entering the sea at the glacier front with the minimum salinities occurred further into the fjord. This indicates that all of the fresh water flow here is as ice, only diluting the sea water as the ice melts on its journey out to the open sea. The sea temperatures were 2°C, 4°C above the freezing point of sea water, and more than sufficient to slowly melt the freshwater of these glacial icebergs.

The omens have been good over the past day with good geo-results, sunny skies and good Northern Lights. Last night as Emily and I prepared the Argo float for deployment today the light show of the sky was joined by a show from the sea with phosphorescent plankton trailing in our wake. The oceans were at last proving to match the other stars of the Cape Farewell show.

Simon Boxall and Emily Venables launch the ARGO float

Simon Boxall and Emily Venables launch Disko-very Bob the ARGO float
Simon Boxall and Emily Venables launch Disko-very Bob the ARGO float.

Early morning and the sweet dulcet tones of Ko to awaken us for the Argo deployment – one of the key aims of the science of the voyage. With mugs of steaming coffee and thick coats to ward off the freezing winds Emily activated the buoy while I tried to communicate with it by laptop. It always astounds me when, in such extreme conditions, everything works first time, and for once it did. Having got our location and actual depths – we never rely totally on the charts which were last updated here over half a century ago – we could do the final programming of the float, and the all important naming. The choice? A mix from Quentin Cooper (onboard) and Tom (not onboard) of “Disko-very Bob”. A suitable choice after last year’s Arty Bob given the musicians onboard this year and our location off Disko Bay.

Disko-very Bob was duly signed by many onboard, probably the most bizarre autographs Kate and Jarvis have penned in their career. In order to clear the float from the side of the hull we used the ship’s crane and an elaborate rope system to launch it at 1150GMT. The float drifted neatly away from the ship and began its long voyage. As it disappeared from view Marcus appeared on deck in pyjamas, pen in hand, ready to write the repost to the joke written last year on Arty Bob. Alas he declined to swim after it to complete his mission, so dear reader you will have to wait for the next Cape Farewell.

The Argo float is one of over 3,000 deployed in the oceans today and is the closest we have put to the North West Passage. It will now sink to 200m to track the West Greenland Current as it heads north. Every five days it will sink to the sea bed and rise to the surface, measuring temperature and salinity on its way. These data will be transmitted via satellite to the team back in Southampton and added to the growing data set from the Argo network. Disko Bob will then sink back to its cruising depth and repeat the cycle for the next 3 years – a true scientific legacy from the voyage. We think it will eventually cut across towards the Canadian coast as it approaches the North West Passage and flow back south on the Baffin coastal current and into the Labrador Sea. The cold and fresher water from here then moves south to meet and counter the warmer, saltier waters of the Gulf Stream.

Leslie Feist signs Disko-very Bob the ARGO float

When can you see the first data? Disko-very Bob should send the first data back as we return from the voyage on Monday/Tuesday. Watch this space.

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    One Comment

    1. Jon Turton

      Posted Thursday 9 Oct at 10:29 | Permalink

      Hello Simon and Emily,

      Many thanks for deploying the Argo float (1150 on 4/10), it made its first profile on 7/10 (see http://www.bodc.ac.uk/projects/international/argo/floats/05558/ ). If possible could you let us know the actual position it was deployed at.

      By the way Arty-Bob is still going strong and is currently the most northerly float in the Argo array!

      cheers

      Jon