Northernmost Gliders Battle Ocean Conditions on the Newfoundland Shelf and Shelfbreak

Memorial University (www.mun.ca; Brad deYoung, Ralf Bachmayer, Robin Matthews, and Brian Claus) and McGill University (www.mcgill.ca; Jaime Palter and Tara Howatt) are our northernmost partners for Gliderpalooza 2014.

They just recovered two gliders that were deployed on the Newfoundland and Labrador Shelf at 54 o N in connection with two programs: Vitals (http://knossos.eas.ualberta.ca/vitals/) and OSNAP (http://www.o-snap.org).

While these latest deployments were successful, the team endured several technical issues with their gliders during their first deployment in July.

The following text is from Brad deYoung that describes the circumstances of those deployments:

“The first deployment of three gliders was at the shelf break near the 53 0N mooring line of OSNAP in July 2014.

CSS Hudson in the background as the glider is inspected by  seabirds. The July 2014 deployment was from the CSS Hudson for which DeYoung thanks their colleagues Blair Greenan and Dave Hebert at the Bedford Institute of Oceanography.
CSS Hudson in the background as the glider is inspected by seabirds. The July 2014 deployment was from the CSS Hudson for which DeYoung thanks their colleagues Blair Greenan and Dave Hebert at the Bedford Institute of Oceanography.

Our plan was to deploy the three gliders and have two criss-cross the shelf break surveying the shelf-break Labrador Current while the third glider sampled inshore on the inner side of the current. This did work, but not quite as well as we had planned. We had to recover one glider early because of a leak problem, and the others had troubles with lighter than expected water at the surface on the shelf that affected the ballast of the gliders. The gliders were in the water for about six weeks, about four weeks short of their intended deployment.

Three gliders were deployed, one shallow (200m – red) and two deep (1000m – yellow and green).
Three gliders were deployed, one shallow (200m – red) and two deep (1000m – yellow and green).

As it turned out, the weather cooperated and we had good positions, and so the recovery went very smoothly. The good news is that a glider recovery does not require a hugely complicated set of instruments (see below), fishing boats are pretty much perfect for the task, and fishermen are very good at finding and retrieving things in the ocean.

Finding a lost glider and bringing it home.
Finding a lost glider and bringing it home.

Beyond some cool data that we are now looking at, we learned some things about flying multiple gliders in strong currents, we improved our iPad App that allows us to monitor the gliders, and we learned some new some new things about glider behaviour and ballasting. The good news for our gliders is that in finding them they still had lots of battery power left and so after a little refurbishment they were ready for another deployment and eager to rejoin Gliderpalooza 2014. You can’t keep a good glider down… or up.”