Monday, November 7, 2011

WEATHERED OUT AT CAPE SHERRIFF, LIVINGSTON ISLAND

Just before 12:00 Noon on Nov. 5th, we arrived as planned at Cape Shirreff. The weather is iffy, with winds blowing 30 kts out of the N-NW; air temperature at 2.7 degrees C; and the barometer reading 993 mb.  After waiting a bit for our best weather window, a first attempt was made to launch a zodiac (Fig. 1), intended for a scout team that would survey the area and check out the research station. A few minutes after the launch, it was clear that conditions were too rough to go any further, and the zodiac was brought back aboard. We held position off Cape Sherriff for the afternoon and through the night, hoping for workable conditions for small boat operations needed to transfer people and gear to open the NOAA Marine Mammal Research Station for the summer season.

Figure 1. Launching a zodiac in rough weather takes excellent coordination of the ship’s crew and technical support team.
The next morning (Sunday, Nov. 6th), winds blew at 15 - 20 kts out of the NE, with choppy seas and a few white caps. A check of the conditions indicated: air temperature = -0.1 degrees C; sea surface temperature (SST) = -0.9 degrees C; and salinity = 33.9 PSU. The barometer reading (986 mb) was far lower than the past few days, indicating a low pressure area and indicating bad weather might be coming our way – and so it was!

By mid-morning, low fog moved in, reducing visibility from the ship and obscuring the land – not safe conditions for small boat operations. By early afternoon, it was snowing and the wind picked up to around 20 kts. Air temperature was 0.5 degrees C; the barometer reading (978 mb) indicated that the low pressure system to the west had moved in ahead of schedule. A panoramic view of Cape Sherriff (Fig. 2) shows the conditions and lay of the land clearly – so near and yet so far away!

Figure 2. Panoramic view of Cape Shirreff from open sea to the east to open sea to the west (left to right in image) assembled from 12 images merged using Adobe Photoshop.

The winds really picked up during the afternoon, blowing 30 - 35 kts. Low clouds moved in and the barometer was at 976 mb and falling. By 5:00 PM, winds were gusting out of the West to 55 kt (Figure 3).  The only good news was that the barometer was starting to move back up!  The wind and weather forecast for tomorrow indicated high winds would continue through the day. 

Figure 3. The ship’s Data Acquisition System (DAS) screen showing wind speeds and gusts up to 50 kts during Nov. 6th.

The Captain (Joseph Abshire), Marine Projects Coordinator (Jullie Jackson), Chief Scientist (me), and lead scientists (Joe Warren and Peter Wiebe) met to discuss options and priorities to work toward the cruise scientific objectives despite the bad weather.  After listening to our recommendations and considering the many competing needs and objectives of the cruise, the Captain decided to steam away from Cape Shirreff and head for our Station 22.  We hope the protected location of the station at the entrance to Gerlache Strait will allow us to occupy our first station, carrying out planned sampling and data collection. Our ETA (Estimated Time of Arrival) for Stn 22 is 5:00 AM on Monday, Nov. 7th.  We left our requests for wake-up calls with the bridge, and headed to our bunks for a short night.

Upon our arrival at Stn 22 in the early morning of Nov. 7th, it was clear that we didn’t have the protection from wind and weather we wanted to carry out our first “training station” of the cruise. Winds were still in the 30+ kt range, with gusts to 50 kts. After some discussion with the Captain and MPC on the bridge, the decision was made to head directly for Palmer Station.  We hope to be able to tie up to the dock by this evening, off-load people and cargo tomorrow, and head back to sea tomorrow evening.

-- Ann Bucklin, University of Connecticut

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