ODEX and will take place about 1000 miles west-southwest of Monterey, 

 California, where horizontal variability will be minimal during October 

 and November 1982. The time was chosen to overlap the change from the 

 summer to winter chlorophyll regimes. The biological-optical model will be 

 merged with an upper-layer model based on the Level 2-1/2 Mellor-Yamada 

 Turbulence Closure Scheme. This model is being modified to permit the 

 inclusion of realistic vertical profiles of the relevant parameters such 

 as the downwelling solar irradiance and chlorophyll. Preliminary versions 

 of the new model have been used to demonstrate the diurnal response of the 

 upper ocean. Comparison with measurements have shown that the upper ocean 

 is sensitive to solar irradiance and (optical) water type. Ships in the 

 ODEX experiment will be R/V FLIP and the R/V ACANIA. Both will be fully 

 instrumented with a complete range of chemical, physical, meteorological, 

 and optical instruments. 



For any large-scale (x >_ 1000 km) oceanic domain, oceangraphic applica- 

 tions of measurements made with a CZCS-type sensor are constrained by 

 the same sampling considerations discussed in the preceding shelf 

 studies; sampling frequency, as governed by orbit parameters and cloud 

 cover, will still vary with latitude and season. In general, we expect 

 to adequately resolve synoptic scale phenomena and obtain statistical 

 descriptions of embedded meso-scale structure, in any given oceanic 

 domain. Near surface optical properties are indirectly related to two 

 prime foci of modern physical oceanography, ocean circulation and mixed 

 layer dynamics/thermodynamics, in several ways, including: 



a. The vertical irradiance attenuation coefficient, k, governs the 

 vertical distribution of heating by incident sunlight. 

 Zaneveld et al., 1981, review the influence of k on vertical 

 density stratification in the mixed layer; they document that, 

 under light winds, vertical temperature structure is signifi- 

 cantly sensitive to k over its range of variability in global 

 water masses. CZCS has been demonstrated to be capable of 

 mapping the distributive patterns of k both in open ocean and 

 coastal waters. Preliminary examination of CZCS imagery 

 suggests that a rich structure in synoptic-scale and meso-scale 

 patterns of horizontal k distributions may pervade nearly all 



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