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H.R. Gordon
Working Group’s recommendations regarding optimal spectral bands, we felt that
the proposed ocean color sensor would face little opposition for inclusion on the
platform. Little did we know. There was fierce opposition to its inclusion. I recall a
presentation to a NASA advisory committee regarding ocean color at which the most
prominent member of the committee made the statement: “I know of no respectable
biologist that thinks this [ocean color] is important.” It is interesting to note that
years later Dick Barber referred to CZCS as one of the seven most important
developments in marine biology in the last 50 years! After much time was spent
trying to get an ocean color instrument on NOSS, the entire NOSS program was
canceled; the first of several such failures. However, the time and effort were not
wasted.
17.7 Back to CZCS
One of the significant problems processing CZCS imagery was the intense amount
of computational resources required. Basically, in 1980 the image processing systems were PDP mini-computers coupled to image display devices. I was fortunate
to work with Otis Brown and Bob Evans at the University of Miami, who developed
a system for SST image processing. However, one of the biggest breakthroughs
for ocean color processing was the development of the VAX computer systems by
DEC. These “super-min” computers enabled the processing of CZCS scenes with
acceptable computation times, and made processing of the entire CZCS data set
a possibility. The Brown-Evans image processing system was ported to the VAX
along with all of the CZCS processing algorithms. This processing system was
then duplicated on a larger scale at GSFC in a joint project with Wayne Esaias,
Chuck McClain and Gene Feldman to process all of the CZCS imagery and demonstrate the full potential of ocean color remote sensing to marine ecology (Esaias
et al., 1986).
17.8 SeaWiFS and MODIS
Between 1984 and 1988 there was much work devoted to flying an improved ocean
color scanner. After several failures, this effort succeeded with the approval of
SeaWiFS as a joint project between NASA and EOSAT, a private, for-profit company. The SeaWiFS sensor was designed solely for the purpose of ocean color, with
a special emphasis on accurate radiometry. Special features included NIR spectral
bands for atmospheric correction, a solar diffuser for on-board calibration, the facility for viewing the moon to monitor the long-term stability of the radiometry, and
increased radiometric sensitivity for better resolution of the water-leaving signal.
The sensor was designed to operate continuously, which greatly increased the data
coverage over CZCS. In addition, in support of SeaWiFS (and later MODIS), a dedicated calibration facility was developed by Dennis Clark (Clark et al., 1997). This
H.R. Gordon
Working Group’s recommendations regarding optimal spectral bands, we felt that
the proposed ocean color sensor would face little opposition for inclusion on the
platform. Little did we know. There was fierce opposition to its inclusion. I recall a
presentation to a NASA advisory committee regarding ocean color at which the most
prominent member of the committee made the statement: “I know of no respectable
biologist that thinks this [ocean color] is important.” It is interesting to note that
years later Dick Barber referred to CZCS as one of the seven most important
developments in marine biology in the last 50 years! After much time was spent
trying to get an ocean color instrument on NOSS, the entire NOSS program was
canceled; the first of several such failures. However, the time and effort were not
wasted.
17.7 Back to CZCS
One of the significant problems processing CZCS imagery was the intense amount
of computational resources required. Basically, in 1980 the image processing systems were PDP mini-computers coupled to image display devices. I was fortunate
to work with Otis Brown and Bob Evans at the University of Miami, who developed
a system for SST image processing. However, one of the biggest breakthroughs
for ocean color processing was the development of the VAX computer systems by
DEC. These “super-min” computers enabled the processing of CZCS scenes with
acceptable computation times, and made processing of the entire CZCS data set
a possibility. The Brown-Evans image processing system was ported to the VAX
along with all of the CZCS processing algorithms. This processing system was
then duplicated on a larger scale at GSFC in a joint project with Wayne Esaias,
Chuck McClain and Gene Feldman to process all of the CZCS imagery and demonstrate the full potential of ocean color remote sensing to marine ecology (Esaias
et al., 1986).
17.8 SeaWiFS and MODIS
Between 1984 and 1988 there was much work devoted to flying an improved ocean
color scanner. After several failures, this effort succeeded with the approval of
SeaWiFS as a joint project between NASA and EOSAT, a private, for-profit company. The SeaWiFS sensor was designed solely for the purpose of ocean color, with
a special emphasis on accurate radiometry. Special features included NIR spectral
bands for atmospheric correction, a solar diffuser for on-board calibration, the facility for viewing the moon to monitor the long-term stability of the radiometry, and
increased radiometric sensitivity for better resolution of the water-leaving signal.
The sensor was designed to operate continuously, which greatly increased the data
coverage over CZCS. In addition, in support of SeaWiFS (and later MODIS), a dedicated calibration facility was developed by Dennis Clark (Clark et al., 1997). This