ITP 3 Deployment Operations

ITP 3 and IMB 07950 were the second Ice Based Observatory (IBO) deployed during JWACS 2005. Without either ship’s propulsion (while a main shaft bearing on the ship was being repaired) or helicopter support (grounded), the personnel and gear were deployed over the port side of the CCGS Louis S St. Laurent onto a small (50 m diameter) 3.35 m thick ice floe after several days of surveying and false starts interrupted by the formation of cracks in the ice.

On August 23, a bridge was built to cross a large (4 m) gap between floes to the ITP deployment site. It took only about 3.5 hours overall to deliver all of the ITP gear to the site, deploy ITP 3, and return with the installation equipment. Meanwhile, deploying IMB 07950 took about an hour and a half to drill the holes and install the sensors and buoy. Subsequently, the wires were covered with snow.

More information and photos on the deployment operation are also available here and at: https://www.whoi.edu/page.do?pid=68121 and https://www.whoi.edu/page.do?pid=68199.

On August 21, an ice floe off the port side of the CCGS Louis S St. Laurent is surveyed to determine thickness of 3.5 m as a candidate for IBO deployment.

Two days later, Rick Krishfield and Ryan begin deployment of the IMB with the installation of the ice thermistor strings.

Hauling gear across a bridge over a frozen melt pond.

John Kemp, Kris Newhall, and Doug Sieberg haul gear across a bridge over a frozen melt pond.

Work begins on drilling a hole for ITP3 while Doug Sieberg installs a snow sounder and air temperature mast for the IMB.

With the IMB installation complete, Kris Newhall, John Kemp, and David Sisco load the ITP wire spool onto the winch apparatus.

John Kemp operates the tag line to the ITP 3 profiler, while Rick Krishfield attaches the instrument brackets to the wire.

The potted cable is attached mechanically and electrically to the buoy package, and the slip bale and modem grounding plates are attached at the end of the potted segment

The potted cable is attached mechanically and electrically to the buoy package (foreground), and the slip bale and modem grounding plates are attached at the end of the potted segment (background).

The mooring is deployed after the ITP 3 surface package is in place, although later plywood covered in snow will be situated under the top float to reduce ablation of the ice floe by the buoy. Photos by Chris Linder.