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TECHNOLOGY UPDATE Scientists Develop New Map Of The World's Sea Floors Scientists have used gravity data from satellites in addition to depth soundings from ships to produce a more defined, high-resolution map of the world's ocean floors, the U.S. National Oceanic and Atmospheric Administration (NOAA) announced. The new map provides estimations of the ocean depths from gravity data from satel- lites. An older version of the map, produced in 1995, was based on gravity data, but did not provide estimations of ocean depths. Scientists Walter H.F. Smith of NOAA's National Oceanographic Data Center and David T. Sandwell of the Scripps Institution of Oceanography, University of California, San Diego, report on their project in the September 26 issue of Science magazine. Filling In The Gaps Conventional sea floor mapping using echo sounding data from ships has been difficult because of the large gaps between surveys in remote areas. "There are places as large as the State of Oklahoma where no soundings are avail- able," said Mr. Smith. "Traditionally, bathy- metric contours are drawn by hand, so that human intuition (or prejudice) fills the gaps in coverage," both scientists wrote in Science. "Recent developments allow a new approach to this problem." Mr. Smith and Mr. Sandwell used gravity data from satellites to estimate depths in unsurveyed areas, thus filling the gaps in the map in an objective and high-resolution man- ner. The new topography reveals all of the intermediate and large-scale structures of the ocean basins, including new mountain ranges such as the Foundation Seamounts in the South Pacific. These were not found by conventional mapping but were revealed by the satel- lite gravity data. The pair of scientists showed that unchart- ed seamounts are a significant source of topo- graphic variation, and information from satellite gravity can reduce the error in esti- mated topographic variation by more than half. Knowledge of sea floor topography is vital for understanding physical oceanography, marine biology, chemistry and geology. Topography influences currents, tides, and mixing and upwelling of nutrient-rich water. The new topographic features portrayed by Mr. Smith and Mr. Sandwell reveal new fish habitats, and should influence computer sim- ulations of ocean circulation. The decking that meets "U.S. Navy, U.S. Coast Guard and Canadian Coast Guard requirements. Insulite is an insulating underlayment ideal for use with terrazzo, carpet, vinyl composition tile, ceramic tile, electrical grade sheet and other comparable overlays. Unlike conventional under- layment, Insulite decking offers: • Superior insulation • Savings in material in a light-weight • Savings in labor application • A-60 approval Make your next decking system more practical and economical. Specify Insulite by E.H. O'Neill Co., Inc. Write today for complete information and specifications: or COMRANV INCORPORATED Serving the industry since 1900 1405 Chippendale Rd„ Lutherville, MD 21093 U.S.A. 410-560-2244 / Fax-410-252-9767 ComNav AUTOPILOTS ... M~l MM - I - y'W STORMPROOF "Whenever sea conditions get worse, so does my autopilot performance." Sound familiar? Not if you own a ComNav Autopilot. Stormproof your steering performance in ALL sea conditions with ComNav Autopilots... the calm during the storm. Call or fax for free brochure: Phone 1-800-428-0212 E-Mail: sales@comnavmarine.com Fax 1-800-470-9611 Website: www.comnavmarine.com Circle 258 on Reader Service Card ComNav Marine Ltd. 1915 Stainsbury Avenue Vancouver, BC, Canada V5N 2M6 Circle 241 on Reader Service Card Wartsild NSD And Cummins Engine Extend Cooperation Wartsila NSD Corp. and Cummins Engine Co. Inc. have signed a letter of intent to extend their cooperation in the heavy- duty high-speed engine business to include engineering, marketing and service of power generation, marine and industrial applications based on these engines. Currently, the parties have a 50/50 owned joint venture, Cummins Wartsila Engine Co., established in 1995 which designs and produces two high-speed diesel and natural gas engine fam- ilies in France and in the U.K. The joint venture will merge the high- speed activities of Wartsila France, a part of the Cummins PGI Company's manufacturing, all the Cummins Wartsila Engine Company activities in France and in the UK and the respective mar- keting service activities of Cummins. The new joint venture will be owned 50/50 by Wartsila NSD and Cummins. Maritime Reporter/Engineering News
