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ESTIMATES OF SURFACE HEATING RATES
The remote measurement of water-leaving radiances not only provides insight into the
biogeochemical processes of the upper ocean; it also provides an estimate of the clarity of the
surface ocean to visible radiation. This is important in the evolution of the upper ocean
thermal structure since the distribution of the absorption of solar radiation with respect to
depth is a key determinant of the heating rate (e.g. Denman, 1973; Lewis et al., 1983; Lewis,
1987; Ackleson et al., 1988; Lewis et al., 1990). Areas of the ocean where high
concentrations of phytoplankton exist permit relatively little solar energy penetration with the
result that most of the solar energy is absorbed and heats the upper few meters. Clearer, open
ocean conditions result in as much as 40% of the energy contained in visible frequencies
pentrating to heat waters deeper than 30 m. The development of thermal structure, such as
the upper mixed layer, is strongly affected on time-scales ranging from the diurnal to the
seasonal and longer. On interannual scales, Lewis et al. (1990) using CZCS derived estimates
of the attenuation coefficient for the Pacific Ocean equatorial basin, demonstrated the
importance of the penetrating irradiance flux in the heat budget of the tropical ocean and the
potential variations induced in air-sea heat exchange by variations in the pigment content of
the upper ocean. For the heating problem, the principal variable of interest is the attenuation
coefficient where more retreival skill exists than is possible with pigment concentration.
OPTICAL MEASUREMENTS FROM ALTERNATE PLATFORMS
Measurement of the color of the sea, and upper ocean optical properties, is not restricted to
satellite observations. For many applications, other platforms are preferable. For example,
for many parts of the world's oceans, including some of the most productive, clouds obscure
the satellite's view for much of the time. Ships, buoys and aircraft can to more or less a
degree, alleviate this, albeit with a loss in the synoptic coverage that the satellite affords.
Higher spatial and temporal resolution is also possible and for ships, buoys and low altitude
aircraft, the error associated with uncertainties in the atmospheric correction is to large extent,
eliminated. Details of the vertical structure of the optical properties in the ocean can be
determined. Power, mass and data rate are also not such great constraints; higher spectral
resolution and consequent improvements via advanced spectroscopic analysis is attainable. Use
ESTIMATES OF SURFACE HEATING RATES
The remote measurement of water-leaving radiances not only provides insight into the
biogeochemical processes of the upper ocean; it also provides an estimate of the clarity of the
surface ocean to visible radiation. This is important in the evolution of the upper ocean
thermal structure since the distribution of the absorption of solar radiation with respect to
depth is a key determinant of the heating rate (e.g. Denman, 1973; Lewis et al., 1983; Lewis,
1987; Ackleson et al., 1988; Lewis et al., 1990). Areas of the ocean where high
concentrations of phytoplankton exist permit relatively little solar energy penetration with the
result that most of the solar energy is absorbed and heats the upper few meters. Clearer, open
ocean conditions result in as much as 40% of the energy contained in visible frequencies
pentrating to heat waters deeper than 30 m. The development of thermal structure, such as
the upper mixed layer, is strongly affected on time-scales ranging from the diurnal to the
seasonal and longer. On interannual scales, Lewis et al. (1990) using CZCS derived estimates
of the attenuation coefficient for the Pacific Ocean equatorial basin, demonstrated the
importance of the penetrating irradiance flux in the heat budget of the tropical ocean and the
potential variations induced in air-sea heat exchange by variations in the pigment content of
the upper ocean. For the heating problem, the principal variable of interest is the attenuation
coefficient where more retreival skill exists than is possible with pigment concentration.
OPTICAL MEASUREMENTS FROM ALTERNATE PLATFORMS
Measurement of the color of the sea, and upper ocean optical properties, is not restricted to
satellite observations. For many applications, other platforms are preferable. For example,
for many parts of the world's oceans, including some of the most productive, clouds obscure
the satellite's view for much of the time. Ships, buoys and aircraft can to more or less a
degree, alleviate this, albeit with a loss in the synoptic coverage that the satellite affords.
Higher spatial and temporal resolution is also possible and for ships, buoys and low altitude
aircraft, the error associated with uncertainties in the atmospheric correction is to large extent,
eliminated. Details of the vertical structure of the optical properties in the ocean can be
determined. Power, mass and data rate are also not such great constraints; higher spectral
resolution and consequent improvements via advanced spectroscopic analysis is attainable. Use