Information Technology Reference
In-Depth Information
The GOME dataset includes different data products, processing levels and asso-
ciated information. The commonly used names and descriptions of these types of
data are as follows:
•
Level 0 - raw data as acquired from the satellite, which is processed to:
•
Level 1 - providing measures of radiances/reflectances. Further processing of this
gives:
•
Level 2 - providing geophysical data as trace gas amounts. These can be
combined as:
•
Level 3 - consisting of a mosaic composed by several level 2 data products with
interpolation of data values to fill the satellite gaps.
The figure below illustrates the processing chain to derive GOME Level 3 data from
Level 0.
Fig. 20.1
The steps of GOME data processing
Figure
20.1
illustrates in more detail the processing chains to derive GOME Level
2 data from Level 0 and GOME Level 1C data from Level 1B.
As shown in Fig.
20.2
an ad-hoc process generates GOME Level 1C data (fully
calibrated data) starting from Level 1 data (raw signals plus calibration data, also
called L1B or L1b data. A single Level 1b data can generate (applying different
calibration parameters as shown in the figure) several different Level 1C products
and so a user asking for GOME Level 1C data will be supplied with L1 data and the
processor needed to generate Level 1C data
20.2 Challenge Addressed
The ESA processing pipeline runs on particular hardware and software systems.
These systems can change over time. While the project is funded, these changes
will be overcome trough porting of software between systems. The challenge is to
achieve preservation by supporting software updates after the end of the satellite
project.
