determine the limitations on the size of acoustic 

 arrays, the signal processing time for acoustic 

 surveillance systems, and the ocean environmen- 

 tal data required for accurate acoustic predictions. 

 Other priority areas in the oceanography pro- 

 gram are: 



• Ground truth verification for satellite remote 

 sensors that can be used to infer ocean con- 

 ditions below the surface, including infrared 

 and microwave sea surface temperature sen- 

 sors, precision altimeters for ocean currents, 

 tides and geoidal heights, scatterometer for 

 wave height, synthetic aperture radar for 

 directional wave spectra. 



• Development of improved control methods 

 for biological fouling and boring growths that 

 will be compatible with tightening EPA regu- 

 lations. The emphasis here must be on repel- 

 lants rather than on today's toxins, such as 

 creosote or organotins. Development of new 

 methods to reduce corrosion by understand- 

 ing seawater chemistry and the formation of 

 biological slimes that are a precursor to cor- 

 rosion in seawater. Corrosion and biodete- 

 rioration presently are a $200-million-a-year 

 problem to the Navy for pier/piling repairs, 

 added fuel, and dry docking costs. 



• Development of the technology for quantita- 

 tive understanding of low-frequency acoustic 

 propagation in the sea floor, including the use 

 of deep sound sources and ocean bottom 

 seismographs. 



• Continuation of refinements of the proce- 

 dures for analysis of trace .organics and inor- 

 ganics in seawater for possible nonacoustic 

 ASW purposes. 



• Development of improved prediction methods 

 for locating sea floor areas where the bathy- 

 metry, gravity, or magnetic field must be sur- 

 veyed in greater detail. Effective geophysical 

 prediction methods will minimize ship time 

 required for ocean surveys. 



Arctic Program 



The objectives of ONR's Arctic program are: 



(1) To gain an improved understanding of environ- 

 mental conditions in the Arctic and of environ- 

 mental factors that affect Arctic naval operations, 



(2) to develop new and improved observational 

 techniques for measuring environmental condi- 

 tions in this area, and (3) to develop improved 

 capabilities for predicting those environmental 

 conditions that have a strong effect on Arctic 

 naval operations. The environmental factors of 

 interest include physical and biological oceano- 

 graphic conditions under the Arctic ice cap, the 

 acoustic transmission characteristics of these wa- 



ter masses, the ambient noise conditions related 

 to the Arctic ice cap, the dynamic relations be- 

 tween Arctic ice and the overlying atmospheric 

 forces and the underlying ocean forces, atmos- 

 pheric factors related to weather forecasting and 

 long-range climate predictions. A number of spe- 

 cific field projects are underway or planned for 

 1977-83 to achieve the above objectives. These in- 

 clude ambient noise model development and field 

 experiments being conducted in the Chukchi Sea 

 and the Beaufort Sea from the Naval Arctic Re- 

 search Laboratory; Arctic acoustic studies con- 

 ducted jointly at sea from Alert, Ellesmere Island, 

 and Nord, Greenland, in concert with the Canadi- 

 ans and the Danes; establishment of Manned- 

 Unmanned Environmental Research Stations 

 (MUMMERS) in various parts of the Arctic, used 

 for a variety of environmental measurements; ini- 

 tiation of the Nansen Drift Station across the Eur- 

 asian Basin over the mid-Arctic ridge to be con- 

 ducted in concert with all circumpolar nations; and 

 East Greenland Drift Stream (a multinational in- 

 vestigation of the dynamic land-air-sea-ice pro- 

 cesses) within the southerly flowing East Green- 

 land drift stream. ONR participation in most of 

 these projects would include among other things 

 acoustics, remote sensing of sea ice, airborne and 

 sea floor geophysics, atmospheric physics related 

 to improved weather forecasts, and ionospheric 

 research related to long-range communications. 



Coastal Geography 



The objective of this program is to achieve a 

 basic understanding of the coastal shallow water 

 environment; an understanding of the terrestrial, 

 oceanic, and atmospheric forces which influence 

 this environment has, as a goal, the ability to 

 predict coastal phenomena that affect amphibious 

 and riverine operations. 



An example of current research in this area is 

 the study of beach and surf zone processes by 

 investigating wave-breaking mechanisms, long- 

 shore currents, nearshore sediment transport, and 

 beach and bottom dynamics. Development of 

 nearshore dynamic models is an important part of 

 the program. 



Another current long-range Navy project con- 

 cerns the design of a computer-based environmen- 

 tal information inventory system for the world's 

 coastal regions. When completed, this system will 

 contain information about data sources, environ- 

 mental characteristics, and prediction models for 

 the world's coastal regions. The development of 

 various coastal prediction models has been part of 

 this project. The long-range plan is to develop 

 master coastal environmental prediction models 

 for world coastal regions, capable of a high de- 



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