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10 MTR March 2006 Commercial Ships for Oceanographic Research As the 36,000-ton ferry Norröna makes its weekly trip from Denmark to Iceland, it not only carries a load of up to 1,500 passengers and 800 automobiles, it will also help scien- tists learn about the movement of warm and cold waters into and out of the Nordic seas. It is the latest among a small group of com- mercial vehicles that oceanographers are enlisting to aid in their research. The vessel is equipped with an acoustic Doppler cur- rent profiler. The device measures the veloc- ity of water moving beneath the ship - from the surface to as deep as 800 m - by calcu- lating the speed and direction of floating zooplankton. Since many merchant vessels travel the same route week after week and year after year, they are ideal for collecting the necessary data. Once it is installed on a ship, the acoustic Doppler current profiler takes measurements without requiring any human assistance. Due to natural variability in the oceans, the Norröna, built in 2003, will likely need to collect data for at least five years to provide enough useful informa- tion to analyze, and even longer than that to determine long-term trends. Other scien- tists has been collecting similar information from the freighter Oleander, which travels between New Jersey and Bermuda and which is equipped with the same instru- mentation in 1992. The first 12 years of data collected by the Oleander demonstrat- ed that the Gulf Stream off the U.S. East Coast is quite stable and varies little. The same data also showed that cold water from the Labrador Sea moves west and exhibits significant variability. Merchant vessels have been used for many years to collect sea sur- face temperature data and weather observa- tions, but more complex measurements have required sending a scientific observer news Visit www.maritimeequipment.com/mt & Click No. 220 2006 International ROV Competition for High School & College Students June 23-25, 2006 NASA Johnson Space Center's Neutral Buoyancy Lab “Ocean Observing Systems: Tools for Tomorrow’s Science & Technology Workforce” For more information contact the MATE Center’s Jill Zande at (831) 646-3082 or jzande@marinetech.org MTR#2 (1-16).qxd 2/23/2006 4:17 PM Page 12