Section III 

 Program Areas 



A. Physical Oceanography Program 



Long-Range Planning 



I. Core Program 



The Physical Oceanography Program is concerned with developing a basic understanding of the 

 circulation of oceans, estuaries, and large lakes. Investigators document water properties and 

 study the motions of water masses and transport processes. They seek to understand the physical 

 properties and boundaries of water masses and the driving forces, such as wind, solar radiation, 

 precipitation, evaporation, the earth's rotation, and solar and lunar tides. The program has been 

 traditionally divided into five topical areas: ocean circulation, coastal and estuarine circulation, 

 ocean/atmosphere coupling, surface and internal waves and tides, and microstructure and 

 turbulence. The heart of the program is the general circulation of the ocean, complementing the 

 central thrusts of the NASA and ONR programs in surface and upper ocean processes, 

 respectively, and the coastal zone programs of MMS, NOAA, Corps of Engineers, and state 

 agencies. 



Recently the major thrust of large physical oceanography projects has been in tropical 

 oceanography. This reflects the rapid development of theoretical models of equatorial circulation 

 and the recognition that, first, these ideas could be tested with observations and, second, 

 atmospheric general circulation seems most sensitive to the condition of surface waters near the 

 equator. 



The near-term direction for physical oceanographic research seems relatively clear based on 

 recent theoretical and technological developments. At least two recent theories of mid- and 

 high-latitude ocean dynamics, namely, ventilation of the main thermocline and the 

 homogenization of potential vorticity, are ripe for further development and testing. Remote 

 sensing techniques (acoustically tracked floats, satellite altimeters and scatterometers, surface 

 drifting buoys) make global sampling possible on meso, synoptic, and gyre scales. Expanded 

 large-scale computing capability and improved ocean circulation models provide new tools for 

 data assimilation and interpretation. The need for improved understanding of ocean circulation 

 for climate studies has stimulated development of two large-scale projects in the international 

 scientific community - the Interannual Variability of the Tropical Ocean and 

 Global Atmosphere Project (TOGA) and the World Ocean Circulation Experiment (WOCE). 



II. Critical Needs of the Core Program 



The categories of critical needs specified in Section II.A all apply to the Physical Oceanography 

 Program. Those which have a significant impact on development and maintenance of basic 

 research capability in physical oceanography in the immediate future are described below in 

 greater detail. 



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