19 January, 2004
The ship left port with volunteer help from McMurdo at 12:30. A small group of McMurdo residents had come to the dock to bid us farewell. It took some time to maneuver away from the ice dock and to move out into the channel. Calm winds for the past 24 hours had allowed the sea ice to reform. As we left dock, the ship broke through clear sea ice laced with filamentous feathers of white crystals.
The crew and marine techs continued to stow cargo and secure gear as we headed out to our first area to be mapped pausing occasionally to take a photo. Everyone got into the act including Captain Mike who has been aboard ships in the Antarctic for more than ten years. We passed two ships on our way out, the Coast Guard Ice Breaker, Polar Sea, as it made its way back into dock at McMurdo, and cargo ship frozen in the ice along the channel waiting to enter the dock with the help of the icebreaker. The cargo ship's gangway was down on the ice and a well-worn footpath was visible from its end across the sea ice.
The fun was short lived. All hands were called to the 03 conference room for an information and safety briefing. Ashley Lowe, the MPC (Marine Projects Coordinator) introduced the marine technicians and technology support staff aboard the ship. Following these introductions and the introductions of the members of the science team, we began our briefing on ship safety. The ships engineer made it clear that those who survive accidents at sea are the ones who are prepared. Each of us practiced putting on our flotation suits made of stretch neoprene. We all waddled out onto the deck and into the lifeboats in our "lobster suits" in our first emergency practice drill of the cruise. We were all encouraged to learn the most direct routes to the gathering areas and lifeboats by the end of the day.
We were then directed to the computer lab for an overview of the network system with the IT staff. The ships network is divided into two main areas. One is called the hotel network and is primarily set up to handle email, and office applications. The science network is connected to all of the data acquisition equipment aboard the ship and is designed to store the data for future analysis using a variety of programs available to the scientists. Email is sent using a satellite data connection and is delivered 2 or 3 times a day. Email attachments are limited due to the cost associated with the satellite connection, but test messages are not a problem.
We were just four hours out of McMurdo and it was nearly time to start collecting our first data, but we needed to be trained in a for Marine Mammal Observing and ping editing. The scientists and marine support staff are very conscientious that the science that is being conducted aboard ship may have the potential to disturb wildlife. The marine mammals that we are likely to encounter are whales, dolphins, and seals. To insure that there is minimal impact on the marine mammals in the area a well established procedure has been established for all research in the ocean along the Antarctic continent.
During our cruise we will have visual observers on the bridge any time we are conducting seismic surveys. If a marine mammal is spotted within a range of less than 200 meters while seismic work is being conducted, the data acquisition will be suspended until the animal leaves the restricted area. Once the animal leaves the area, we can begin collecting data again. The principle scientists aboard the cruise have been waiting over two years to begin the cruise, but they are more than willing to make sure that their geological surveys of the area have limited impact on the wildlife.
Following our first dinner as a group aboard the ship, we wrapped up our orientation with a lesson on beam editing. As the ship is moves on the course planned by the scientists, data bout the surface features of the seafloor is collected using multibeam sidescan sonar. >From the bottom of the ship, a sound pulse is produced. This pulse travels down through the water and then is reflected off of the bottom. It reflects back up to the surface where receivers on the bottom of the ship detect the reflected sound waves. Computers collect time data from the detectors and store that for analysis. Each of pulse produces a record about the surface of the seafloor below the ship at the time of the pulse. These pieces of data are called beams or pings. Any outliers in the data are removed in the beam editing process. These clean beams can then be plotted by the scientist to produced detailed contour maps of the seafloor.
We began collecting our first data at about 7:00 ship time.
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