Chapter 18
Field Radiometry and Ocean Color Remote
Sensing
Giuseppe Zibordi and Kenneth J. Voss
18.1 Introduction
In the eighteenth century the experimental and theoretical work of Pierre Bauger
and Johann Lambert in the area of light measurements led to the formulation of
basic theories such as the law of addition, the inverse square law and the cosine
law of illumination (Johnston, 2001). Despite these advances, the first successful measurements of marine light were only performed in the 1920s (Kundsen,
1922; Shoulejkin, 1924; Pettersson and Landberg, 1934; Jerlov and Liljequist,
1938) followed by a substantial progress in understanding marine optical processes, in producing theories to quantitatively describe the in-water light field and
in defining fundamental laws and methods for underwater optics (Gershun, 1939;
Le Grand, 1939).
After the first pioneering phase, advancements in marine light measurements
were successively linked to progresses in quantitative optical radiometry culminating with the definition of basic designs for spectral radiometers (Jerlov, 1951;
Steeman Nielsen, 1951) and in the realization of light detectors and of standards for
absolute spectral calibration (Tyler and Smith, 1970; Slater, 1980).
In the 1980s, with the introduction of satellites for the remote observation of
ocean color to map marine phytoplankton biomass at a global scale, in-situ optical radiometry became a basic component of the first ocean color mission (i.e., the
Coastal Zone Color Scanner (CZCS)). While satellite radiometry provided global
synoptic observations of the radiance emerging from the sea, in-situ radiometry
was required to develop algorithms linking the satellite observations to the optically significant seawater components (Kirk, 1994; Mobley, 1994; Spinrad et al.,
1994).
Major developments in in-situ marine optical radiometry were then driven by
the need to reduce the uncertainties in field measurements for their application
in advanced bio-optical modeling, vicarious calibration of satellite sensors and
G. Zibordi (B)
Institute for Environment and Sustainability, Joint Research Centre, European Commission,
Ispra 21027, Italy
e-mail: giuseppe.zibordi@jrc.ec.europa.eu
307
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_18, C
Springer Science+Business Media B.V. 2010
Field Radiometry and Ocean Color Remote
Sensing
Giuseppe Zibordi and Kenneth J. Voss
18.1 Introduction
In the eighteenth century the experimental and theoretical work of Pierre Bauger
and Johann Lambert in the area of light measurements led to the formulation of
basic theories such as the law of addition, the inverse square law and the cosine
law of illumination (Johnston, 2001). Despite these advances, the first successful measurements of marine light were only performed in the 1920s (Kundsen,
1922; Shoulejkin, 1924; Pettersson and Landberg, 1934; Jerlov and Liljequist,
1938) followed by a substantial progress in understanding marine optical processes, in producing theories to quantitatively describe the in-water light field and
in defining fundamental laws and methods for underwater optics (Gershun, 1939;
Le Grand, 1939).
After the first pioneering phase, advancements in marine light measurements
were successively linked to progresses in quantitative optical radiometry culminating with the definition of basic designs for spectral radiometers (Jerlov, 1951;
Steeman Nielsen, 1951) and in the realization of light detectors and of standards for
absolute spectral calibration (Tyler and Smith, 1970; Slater, 1980).
In the 1980s, with the introduction of satellites for the remote observation of
ocean color to map marine phytoplankton biomass at a global scale, in-situ optical radiometry became a basic component of the first ocean color mission (i.e., the
Coastal Zone Color Scanner (CZCS)). While satellite radiometry provided global
synoptic observations of the radiance emerging from the sea, in-situ radiometry
was required to develop algorithms linking the satellite observations to the optically significant seawater components (Kirk, 1994; Mobley, 1994; Spinrad et al.,
1994).
Major developments in in-situ marine optical radiometry were then driven by
the need to reduce the uncertainties in field measurements for their application
in advanced bio-optical modeling, vicarious calibration of satellite sensors and
G. Zibordi (B)
Institute for Environment and Sustainability, Joint Research Centre, European Commission,
Ispra 21027, Italy
e-mail: giuseppe.zibordi@jrc.ec.europa.eu
307
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_18, C
Springer Science+Business Media B.V. 2010