First Paragraph
Ocean optics concerns studies of light and its propagation through the ocean, and bio-optics connotes biological effects on optical properties and vice versa. These two terms are so intertwined that they are often used interchangeably. Knowledge of the variability of optical and bio-optical properties of the ocean is important for many scientific and practical problems (e.g., Dickey and Falkowski, 2001). A few examples follow. Light and its utilization is key to life in the ocean beginning with phytoplankton and primary productivity, the ecology of the upper ocean, and biogeochemical cycling. The thermal structure and heat budget of the upper ocean are driven by the penetration of solar radiation as modulated by the absorption and scattering of light by water and its particulate and dissolved constituents. Both of the aforementioned examples illustrate key factors that affect and are affected by global climate change. Optical properties are also important indicators of the health of the ocean in the form of changing turbidity, diversity and distributions of species (indigenous and non-indigenous), and harmful algal blooms (e.g., red tides) and associated toxins. Underwater visibility, which has industrial and military relevance, also depends on optical properties. Importantly, in situ optical sensors and systems allow us to study a host of oceanographic processes, which bear on these and other problems as well as a variety of interests including quantification and interpretation of satellite- and aircraft-based observations of ocean color and studies of sediment resuspension, pollution, and bathymetry. Readers interested in learning more about the subdisciplines of ocean optics and bio-optics are directed to other papers in this volume and books by Kirk (1994), Spinrad et al. (1989), and Mobley (1994). Other papers focus on new technologies applied to ocean optics and bio-optics (e.g. Dickey, 1991, 2001; Dickey et al., 1998a, 2001; Maffione, this issue) and biogeochemistry (e.g. Tokar and Dickey, 2000; Varney, 2000; Dickey et al., 2000, 2001).