Chapter 7: APPLICATIONS
which are independent of the incident light field, and are determined entirely
by the type and concentration of substances present in the upper ocean water.
The relationship between ocean color and inherent optical properties of
seawater is consequently of great interest for the interpretation of remote
sensing data. The inherent optical characteristics of the ocean in application
to remote sensing are discussed in more detail in the next section.
7.2 Marine Optics
7.2.1 Inherent optical characteristics of the upper ocean water
Remote sensing of ocean color requires understanding the optical
properties in the upper ocean water. Optical properties of the near-surface
ocean water can be separated into the properties of pure water and the
properties of the dissolved and suspended matter. The presence of dissolved
salts in the water only slightly modifies its optical properties; which,
nevertheless, can make a difference for certain applications. Suspended
matter can influence the light propagation in a more significant way.
Three main components influencing the optical properties of seawater in
addition to pure water itself and the light reflection off the bottom (in coastal
areas) are as follows (IOCCG, 2000):
Phytoplankton (which also includes other phytoplankton
microscopic organisms);
Inorganic suspended material;
Yellow substances represented by colored, dissolved, organic
substances and “detail” particulate material (the latter generally
has absorption characteristics similar to yellow substances).
waters by distinguishing three major water types (I, II, and III), two
intermediate types (IA and IB), and coastal turbidity types (1, 3, 5, 7, 9).
Morel and Priuer (1977) partitioned the oceanic waters into Case 1 and Case
2 water. They defined Case 1 waters as those waters in which phytoplankton
and accompanying biochemical and particulate environment are mainly
responsible for variations in optical properties of the water. Case 2 waters,
according to their classification, are the waters that are also influenced by
inorganic particles in suspension and yellow substances.
The inherent optical properties of the water that are relevant to remote
sensing of the ocean color are the absorption and scattering coefficients,
which describe the exponential rate of decay of flux per unit path length of
light in the water due to absorption and scattering of light, respectively. The
observed color of the ocean results from the interaction of incident flux
(downwelling, direct-solar and diffuse-sky, irradiances) with water and with
its organic and inorganic substances. The processes of absorption and
451
Jerlov (1976) proposed an optical classification of oceanic surface
which are independent of the incident light field, and are determined entirely
by the type and concentration of substances present in the upper ocean water.
The relationship between ocean color and inherent optical properties of
seawater is consequently of great interest for the interpretation of remote
sensing data. The inherent optical characteristics of the ocean in application
to remote sensing are discussed in more detail in the next section.
7.2 Marine Optics
7.2.1 Inherent optical characteristics of the upper ocean water
Remote sensing of ocean color requires understanding the optical
properties in the upper ocean water. Optical properties of the near-surface
ocean water can be separated into the properties of pure water and the
properties of the dissolved and suspended matter. The presence of dissolved
salts in the water only slightly modifies its optical properties; which,
nevertheless, can make a difference for certain applications. Suspended
matter can influence the light propagation in a more significant way.
Three main components influencing the optical properties of seawater in
addition to pure water itself and the light reflection off the bottom (in coastal
areas) are as follows (IOCCG, 2000):
Phytoplankton (which also includes other phytoplankton
microscopic organisms);
Inorganic suspended material;
Yellow substances represented by colored, dissolved, organic
substances and “detail” particulate material (the latter generally
has absorption characteristics similar to yellow substances).
waters by distinguishing three major water types (I, II, and III), two
intermediate types (IA and IB), and coastal turbidity types (1, 3, 5, 7, 9).
Morel and Priuer (1977) partitioned the oceanic waters into Case 1 and Case
2 water. They defined Case 1 waters as those waters in which phytoplankton
and accompanying biochemical and particulate environment are mainly
responsible for variations in optical properties of the water. Case 2 waters,
according to their classification, are the waters that are also influenced by
inorganic particles in suspension and yellow substances.
The inherent optical properties of the water that are relevant to remote
sensing of the ocean color are the absorption and scattering coefficients,
which describe the exponential rate of decay of flux per unit path length of
light in the water due to absorption and scattering of light, respectively. The
observed color of the ocean results from the interaction of incident flux
(downwelling, direct-solar and diffuse-sky, irradiances) with water and with
its organic and inorganic substances. The processes of absorption and
451
Jerlov (1976) proposed an optical classification of oceanic surface