R/V OCEANUS Cruise OC337 Cruise Report

ACKNOWLEDGMENTS

We thank the captain, officers, and crew of the R/V OCEANUS for a very productive cruise; their skill, professionalism, and friendly cooperation enabled us to complete the cruise with all of the scientific missions successfully accomplished.

This report was prepared by Richard Limeburner. This cruise was sponsored by the National Science Foundation and the National Oceanographic and Atmospheric Administration.

GLOBEC R/V Oceanus 337

Woods Hole to Georges Bank to Woods Hole

February 27 - March 2, 1999

Purpose

The objectives of this cruise were to 1) recover the toroid mooring at the NFS site on the northeastern flank of Georges Bank, 2) deploy an NFS discus buoy with meteorological sensors and the toroid subsurface instrumentation, 3) deploy a guard buoy with surface Seacat/Argos at the EF site, 4) recover the VPR profiler at the NFS site, and weather permitting attach an Argos transmitter to the EF toroid buoy. WHOI personnel on the cruise were L. Goepfert, B. Guest, L. Costello, R. Handy, R. Limeburner, J. Lord, and W. Ostrom. Mark Lovewell of the Vineyard Gazette also joined the cruise.

Log

The R/V Oceanus cruise 337 departed Woods Hole on February 27, 1999 at 0945 (all times in this report are EST). We arrived at the NFS mooring site on 2/28/99 at 0430 and prepared to recover the NFS toroid buoy. The acoustic release did not respond or release the anchor so the mooring was recovered and the anchor and ground chain were manually disconnected below the acoustic release. The anchor was off the bottom when the acoustic release came out of the water implying 42 m of ground chain was in a knot. All the subsurface instrumentation was in good shape but the toroid wind speed and direction sensors were damaged. We redeployed the subsurface instrumentation under the discus buoy (instrument with new IMET sensors) at 1156 on 2/28/99. Brian Guest then interrogated the NFS discus release and the release was communicating properly. We next released the VPR floats at 1313. The floats first surfaced and then disappeared due to the strong tidal current. A decision was made to wait until 1600 for a decrease in the strength of the tidal current. The tidal current weakened and we had the VPR floats on deck at 1530 and the VPR was on deck at 1555 on 2/28/99.

We arrived at the EF site about 1900 on 2/28/99 and observed the toroid had drifted about 1.5 miles southwest of the position prior to the storm on 2/25/99. The EF toroid appeared to be down about 4" at the waterline and we assumed the ground chain on this toroid was also knotted. The EF guard buoy was deployed on 3/1/99 at 0030 about 300m east of the EF toroid buoy. See below for the mooring positions. Gale force winds were predicted that night and on 3/1/99 so we then steamed to the NEP site to visually inspect J. Irish's moorings. The moorings were on position and one guard buoy light was not working. We then steamed slowly for Woods Hole with strong southeast winds and arrived in Woods Hole at 0845 on 3/2/99.