HARP Site C: 72° 47.926 N, 158° 23.913 W in 327 meters of water and; HARP Site B, 72° 27.645 N, 157° 23.947 W in 234 meters of water.

The HARP site (or the patch test site -- see below) may be the location for launch of the seaglider.

Upon retrieval of the HARP buoys we will proceed to the edge of the Chukchi Cap (approximately 175 miles from Barrow) and take a deep CTD to calibrate the XBT's. We will the proceed with a Seabeam calibration (Patch Test) steaming back and forth at the base of the Cap and then up and down the slope of the cap. This should take approximately 12 hours.

Depending on the progress of the LSL we will then either rendevous with the LSL or proceed up north to a the region between the Chukchi and the Alpha-Mendeleev to look for the foot of the slope. As usual we cannot predict where we will go as we will be following the bottom.

Should the State Dept decide that we should recover the Chinese mooring we would probably do that before heading north (or instead of) as the mooring is located near the patch test site.

When we have joined up with the LSL we will be collecting multibeam and subbottom data and breaking ice ahead of them along the tracks outlined in the enclosed figures. We will require at least two XBT's per day -- the METOC program may require more.

Ancillary programs (METOC, ice buoy, etc.) will be carried on a non-interference basis as time permits.

There will most likely be numerous exchanges between LSL and HEALY scientists - via LSL helo's.

ANCILLARY PROGRAMS:

HARP RECOVERY AND REDEPLOYMENT:

Recovery - Transit to site C (72° 47.926 N, 158° 23.913 W in 327 meters of water, once we arrive, use an acoustic deck box connected to the 12 kHz hull transducer in IC/Gyro to transmit for range and then release the ballast weights. Approximately 5-10 minutes later, the HARP will surface. Once visually sighted, a small rhib boat will be deployed in order to tow the frame up near the starboard quarter where Healy can crane the instrument onto the aft deck (weighs ~1100 lbs). The same will be repeated for site B (772° 27.645 N, 157° 23.947 W in 234 meters of water). .

Redeployment - Both instruments will be refurbished and made ready for deployment (weighs ~1500 lbs). New sites may be chosen depending on evaluation of the recovered data, so it would be useful to use the multibeam and perform an initial run over the site in order to check for seafloor features like ice scour pocks. Then Healy will position 50-100 meters outside the proposed site and move downswell/wind at about 1 knot (dependent on currents). On the fantail deck, the HARP frame will be positioned underneath the aft A-frame and the 10 meter hydrophone line will be strung out down to the water line. The A-frame operator will lift the frame and pay out until it is submerged below the water line. If everything is streaming properly, then the quick release will triggered and the HARP is deployed on site. If time permits, a XBT sonobuoy will be deployed to collect temperature profiles at each site.

Sonobuoy ops - In order to receive VHF signals from deployed sonobuoys, a vertical antenna will be mounted above the Helo Control Tower and radio gear set up in the Helo Shack. Deployment simply requires gently tossing the expendable hydrophone into the water from the fantail deck. A contingent of sonobuoys will be used to opportunistically record marine mammals like ice seals whenever they are visually sighted from the bridge. Most of the sonobuoys will be used to conduct radiated noise measurements of Healy in various modes of propulsion (i.e. during heavy ice breaking, different prop pitch variations, etc.). The op requires an observer to visually monitor the sonobuoy float and make regular estimations of it's approximate distance from Healy's stern. At the same time, GPS coordinates of Healy's position must also be regularly recorded. These two positions will give the approximate range from source to receiver. It's also possible that two sonobuoys can be deployed and recorded simultaneously if this helps to make more accurate measurements. All sonobuoy calibration will occur on the digital end, so no ops are required for this.

METOCEAN BEACONS/BUOYS

Pre-loading of IABP open ocean drifting buoys and tools will take place in the Seattle or Everett area in June. Coordination of shipment is being done by Ignatius Rigor of the Polar Science Center (PSC). Drifting buoys will be deployed in open water during the most western tracks of the cruise. A total of 2 (two) AXIB seasonal ice buoy prototypes will also be shipped by Legnos Boat, Inc. (LBI) for testing and possible deployment in the marginal ice zone or open water. None of these deployments should require on ice operations. Although unlikely, depending on need, opportunity, and sea ice conditions encountered, one of the seasonal buoys may instead be deployed on multiyear sea ice (MYI). In this case, the deployment on MYI will be scheduled, when possible, to take advantage of other planned stops but in all cases will be conducted strictly as independent and separate field activities from other cruise plans. Typical deployments on MYI take 30-45 minutes of on-the-ice time. All buoy deployments will be done in close coordination with the cruise Chief Scientist on a non-interference basis so as not to impact mapping activities. A pre-cruise nowcast analysis of sea ice conditions in the Beaufort Sea and Chukchi Cap region will be provided by the NIC to the Chief Scientist to guide in the fine tuning of the initial cruise tracks. In addition to on board sea ice analysis and imagery cruise support, the NIC personnel will collect hourly observations of sea ice characteristic as the Healy navigates ice infected waters. Recorded observations will include estimates of ice thickness and snow depth during icebreaking operations in the ice pack. NIC personnel will additionally support the science seminars series during the cruise. Tools and any buoys not deployed during the cruise will be unloaded in Seattle for shipment back to PSC and LBI.

DREDGING:

If time and conditions permit and appropriate target found, we will deploy a dredge and attempt recover in-situ samples of bedrock along sloping targets at approximately 3000 m depth. We will follow standard dredging procedure, deploying the dredge at the bottom of the slope and steaming up slope. If needed we will break the ice along the track before deploying dredge.

UAS OPS:

UAS Operations (should permission be granted) will be on a non-interference basis under the supervision of Greg Walker from the University of Alaska Fairbanks.