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120 OCEANOGRAPHY IN THE NEXT DECADE 



However, these models have received little or no testing in the 

 laboratory or through field observations. 



Muddy sediments are geologically relevant, and some research 

 has been conducted on the transport of low concentrations of 

 fine-grained sediments. Dense concentrations [>10 grams per li- 

 ter (i.e., fluid muds)] are also observed in the marine environ- 

 ment, and their transport is poorly understood. 



Carbonate sediments are widespread at low latitudes, but the 

 effects of physical processes on their dispersal have not been thor- 

 oughly studied. Differences in the particle shapes and densities 

 of carbonate sediments from more common sources make it diffi- 

 cult to extrapolate existing theory of sediment transport. 



Theory regarding the formation of sediment layering within 

 the seabed and its dependence on sediment transport and biologi- 

 cal activity has evolved rapidly. Additional laboratory and field 

 documentation is needed to link formative mechanisms and pre- 

 served strata. 



The overall importance of the coastal ocean extends far be- 

 yond its relatively small areal extent. An environment of remark- 

 ably high biological productivity, this transition zone between 

 land and open ocean is of considerable importance for recreation, 

 waste disposal, and mineral exploitation. Such societal issues as 

 pollution (in its many forms), bioremediation, waste disposal, and 

 risk assessment cannot be addressed adequately until we make 

 substantial advances in our basic understanding of the coastal 

 ocean. A holistic approach to the coastal ocean system, blending 

 marine meteorology with biological, chemical, geological, and physical 

 oceanography, should enable us to progress sufficiently so that we 

 will be better prepared to make the technical and policy decisions 

 facing us over the next decades. Four issues of particular impor- 

 tance are air-sea interactions, cross-margin transport, carbon cycles, 

 and particle dynamics. A balanced program would mclude stud- 

 ies focused on specific processes, long-term measurements, mod- 

 eling, and instrumentation development. To take best advantage 

 of the results of these studies, strong working relationships with 

 the applied science communities need to be forged. 



Coastal measurements will be an important part of a global 

 ocean observing system because it is at the coasts that most countries, 

 particularly developing nations, will make most of their measure- 

 ments. Therefore, it is essential that the design of a COOS in- 

 clude coastal measurements as a critical element of the system. 



