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Mixed-Layer Optical Properties 
Recent studies of mixed-layer dynamics have 
shown that it is essential to characterize the opti- 
cal properties of the upper water column. The 
absorption of solar radiation and its variation with 
depth can greatly affect the vertical stability of 
the water column, and variations in pigment con- 
centration are largely responsible for variations 
in optical properties in most of the world's 
oceans. The stability of the water column has a 
major effect on primary production by controlling 
nutrient Supply and the effective solar radiance 
captured by the phytoplankton. Vertical mixing 
a 
may influence the air-sea interaction and the cli- 
mate. The availability of global data on marine 
so affects sea-surface temperature and, hence, 
optical properties, combined with global sea- 
surface temperature and wind measurements, 
will improve our understanding of the complex 
interaction between physical and biological 
properties in the upper ocean. 
Flow Visualization 
An often-overlooked contribution of satellite- 
acquired imagery of ocean color or temperature 
fields to oceanographic research lies in the op- 
portunity it offers to visualize flow fields. It is dif- 
ficult to quantify such a contribution, but often 
the insight gained by examining a satellite image 
gives rise to new discoveries. For example, en- 
trainment of streamers around a large warm- 
core eddy can be observed in the CZCS imagery 
