29. VEGETATION: AN EARTH OBSERVATION SYSTEM TO
MONITOR THE BIOSPHERE
295
Finally, the simultaneity between the VEGETATION acquisition and the
High Resolution Instrument acquisition, giving the same measurements
(same spectral bands) allow ‘zooming’ on some areas where models for
interpretation of VEGETATION data can benefit from a detailed knowledge
of the ground cover. Use of both types of acquisition give full access to the
high frequency (once a day) and high spatial resolution (20 m).
3.2
The ground segment
Data are received from the satellite in a station located in Sweden and
transmitted to the Archiving and Processing Center located in Belgium,
where all products are generated. Satellite Control and Data Quality are done
from France.
From the beginning of the Program, users were involved to define its
characteristics and the products it should deliver: they are adapted to the
particular missions described above and coherent as much as possible with
the needs of existing projects. Two general categories of users could be
identified:
research teams which are developing methodologies for the use of
VEGETATION data or scientific biosphere studies: they generally have
a study site (about 500 x 500 km2) and need long time series (one year
of daily or weekly data),
projects which are based on the use of both VEGETATION and other
data sets, for which the data delivery has to be fully operational and for
long periods, for comparison or historical studies (one continent every
day). Typically, these projects include MARS, TREES, IGBP, etc.
To illustrate the special characteristics of the instrument, high priority
was given to design products that would allow direct multi-temporal
registration as well as simple superposition with simultaneously acquired
high-resolution data.
VGT-P products: They are adapted for the first type of users for which
physical quality of data is important. They correspond to data which would
have been acquired by an ideal instrument: they are corrected for system
errors (mis-registration of the different channels, calibration of all the
detectors along the line-array detectors for each spectral bands) and resampled to geographic projections for multi-temporal analysis as well as for
comparison with high resolution data. Annotations giving full information
on applied corrections (calibration information, geometric parameters taking
into account attitude and position on the orbit), or for further non-system
corrections (“standard” atmosphere parameters) are attached to the data sets.
1.
2.
MONITOR THE BIOSPHERE
295
Finally, the simultaneity between the VEGETATION acquisition and the
High Resolution Instrument acquisition, giving the same measurements
(same spectral bands) allow ‘zooming’ on some areas where models for
interpretation of VEGETATION data can benefit from a detailed knowledge
of the ground cover. Use of both types of acquisition give full access to the
high frequency (once a day) and high spatial resolution (20 m).
3.2
The ground segment
Data are received from the satellite in a station located in Sweden and
transmitted to the Archiving and Processing Center located in Belgium,
where all products are generated. Satellite Control and Data Quality are done
from France.
From the beginning of the Program, users were involved to define its
characteristics and the products it should deliver: they are adapted to the
particular missions described above and coherent as much as possible with
the needs of existing projects. Two general categories of users could be
identified:
research teams which are developing methodologies for the use of
VEGETATION data or scientific biosphere studies: they generally have
a study site (about 500 x 500 km2) and need long time series (one year
of daily or weekly data),
projects which are based on the use of both VEGETATION and other
data sets, for which the data delivery has to be fully operational and for
long periods, for comparison or historical studies (one continent every
day). Typically, these projects include MARS, TREES, IGBP, etc.
To illustrate the special characteristics of the instrument, high priority
was given to design products that would allow direct multi-temporal
registration as well as simple superposition with simultaneously acquired
high-resolution data.
VGT-P products: They are adapted for the first type of users for which
physical quality of data is important. They correspond to data which would
have been acquired by an ideal instrument: they are corrected for system
errors (mis-registration of the different channels, calibration of all the
detectors along the line-array detectors for each spectral bands) and resampled to geographic projections for multi-temporal analysis as well as for
comparison with high resolution data. Annotations giving full information
on applied corrections (calibration information, geometric parameters taking
into account attitude and position on the orbit), or for further non-system
corrections (“standard” atmosphere parameters) are attached to the data sets.
1.
2.