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SST record 50 km cell MDS
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ATS_TOA_1P_MDSR_conf
ATS_TOA_1P_MDSR_cl
ATS_TOA_1P_ADSR_pix
ATS_SST_AX_GADSR
Vegetation fraction for Land Surface Temperature Retrieval GADS
Topographic Variance data for Land Surface Temperature Retrieval GADS
Land Surface Temperature retrieval coefficients GADS
General Parameters for Land Surface Temperature Retrieval GADS
Climatology Variance Data for Land Surface Temperature Retrieval GADS
Level 0 SPH
Level 0 MDSR
Auxilliary Data SPH with N = 1
1.6 micron nadir view MDS
Summary Quality ADS
Scan pixel x and y ADS
Grid pixel latitude and longtitude topographic corrections ADS
Across-track Band Mapping Look-up Table
Configuration Data GADS
Processor configuration GADS
LST record 50 km cell MDS
Distributed product MDS
Level 2 SPH
SPH
10-arcminute mds
Limits GADS
Validation Parameters GADS
BT/TOA Land record 17 km cell MDS
General Parameters GADS
Temperature to Radiance LUT GADS
Radiance to Brightness Temperature LUT GADS
Medium/High Level Test LUT GADS
Infrared Histogram Test LUT GADS
11 Micron Spatial Coherence Test LUT GADS
11/3.7 Micron Nadir/Forward Test LUT GADS
11/12 Micron Nadir/Forward Test LUT GADS
Characterisation GADS
Browse Day_Time Colour LUT GADS
Browse SPH
Grid pixel latitude and longtitude topographic correction ADS
Level 2 SPH
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ATS_VC1_AX: Visible Calibration data
ATS_SST_AX: SST Retrieval Coeficients data
ATS_PC1_AX: Level-1B Processing configuration data
ATS_INS_AX: AATSR Instrument data
ATS_GC1_AX: General Calibration data
ATS_CH1_AX: Level-1B Characterization data
ATS_BRW_AX: Browse Product LUT data
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ATS_NL__0P: AATSR Level 0 product
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ATS_AST_BP: AATSR browse image
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ATS_TOA_1P: AATSR Gridded brightness temperature and reflectance
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ATS_NR__2P: AATSR geophysical product (full resolution)
ATS_MET_2P: AATSR Spatially Averaged Sea Surface Temperature for Meteo Users
ATS_AR__2P: AATSR averaged geophysical product
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SST record 17 km cell MDS
Surface Vegetation class for Land Surface Temperature Retrieval GADS
1.6 micron forward view MDS
12 micron nadir view MDS
12 micron forward view MDS
Summary Quality ADS
Surveillance Limits GADS
Master Unpacking Definition Table GADS
1.6 micron Non-Linearity Correction LUT GADS
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Thin Cirrus Test LUT GADS
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1.6 Micron Histogram
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ATS_CL1_AX: Cloud LUT data
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ATS_TOA_1P_ADSR_sa
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LST record 17 km cell MDS
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12 Micron Gross Cloud Test LUT GADS
ATS_PC2_AX: Level-2 Processor Configuration data
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6.6.15 Characterisation GADS

Characterisation GADS

This product contains miscellaneous parameters used by the Level 1B processor, including instrument and geodetic parameters and parameters required by the regridding algorithm. It comprises a Main Product Header, a standard Auxiliary Data SPH with one DSD, and the Level 1b Characterisation Data GADS as described in the following table.


Table 6.43 Characterisation GADS

Characterisation GADS

# Description Units Count Type Size
Data Record
0 cone_angle
cone angle

The apex angle of the conical scan of aatsr, in radians. This is the angle between the line of sight and the scan axis.

radians 1 fl 4 byte(s)
1 mir_off
mirror offset angle

The azimuthal offset of the scan from its nominal position, in radians. This is the angle between the nominal and actual mirror positions a the start of the scan.

radians 1 fl 4 byte(s)
2 x_misalign_corr
x misalignment correction

One of the three angles that define the misalignment between the instrument and the spacecraft. The misalignment is specified by the angular rotations about three orthogonal axes required to bring the instrument into nominal alignment with the spacecraft platform. This is the rotation about the x axis, in radians.

radians 1 fl 4 byte(s)
3 y_misalign_corr
y misalignment correction

One of the three angles that define the misalignment between the instrument and the spacecraft. The misalignment is specified by the angular rotations about three orthogonal axes required to bring the instrument into nominal alignment with the spacecraft platform. This is the rotation about the x axis, in radians.

radians 1 fl 4 byte(s)
4 z_misalign_corr
z misalignment correction

One of the three angles that define the misalignment between the instrument and the spacecraft. The misalignment is specified by the angular rotations about three orthogonal axes required to bring the instrument into nominal alignment with the spacecraft platform. This is the rotation about the x axis, in radians.

radians 1 fl 4 byte(s)
5 aocs_cx
AOCS parameter Cx

The AOCS rotation amplitude in pitch. This defines the rotation in pitch applied by the ENVISAT attitude control system in yaw steering mode, according to the formulae set out in the Mission Conventions Document (GS-0561).

deg. 1 db 8 byte(s)
6 aocs_cy
AOCS parameter Cy

The AOCS rotation amplitude in roll. This defines the rotation in roll applied by the ENVISAT attitude control system in yaw steering mode, according to the formulae set out in the Mission Conventions Document (GS-0561).

deg. 1 db 8 byte(s)
7 aocs_cz
AOCS parameter Cz

The AOCS rotation amplitude in yaw. This defines the rotation in yaw applied by the ENVISAT attitude control system in yaw steering mode, according to the formulae set out in the Mission Conventions Document (GS-0561).

deg. 1 db 8 byte(s)
8 aocs_pitch_mis
AOCS pitch mispointing

The constant component of pitch error (if any) of the ENVISAT attitude control system in yaw steering mode. This is applied as a correction during geolocation.

deg. 1 db 8 byte(s)
9 aocs_roll_mis
AOCS roll mispointing

The constant component of roll error (if any) of the ENVISAT attitude control system in yaw steering mode. This is applied as a correction during geolocation.

deg. 1 db 8 byte(s)
10 aocs_yaw_mis
AOCS yaw mispointing

The constant component of yaw error (if any) of the ENVISAT attitude control system in yaw steering mode. This is applied as a correction during geolocation.

deg. 1 db 8 byte(s)
11 earth_maj_axis
EARTH_MAJOR_AXIS

The semi-major axis of the geodetic reference ellipsoid used for AATSR image geolocation. For the WGS 84 ellipsoid it is 6378.137 km.

km 1 db 8 byte(s)
12 atrk_samp_int
Along-track sampling interval

Redundant parameter, no longer used.

km 1 db 8 byte(s)
13 uni_time
Uniform time step

The time interval corresponding to 1 granule, or 32 scans. This is 32 times the scan interval, or 32 times 150 ms, expressed in days. It defines the internal sampling interval used by the geolocation algorithm.

days 1 db 8 byte(s)
14 img_row
Number of image rows per granule

This parameter defines the length of the product granule in image rows; the adopted value is 32.

- 1 sl 4 byte(s)
15 grid_row
Number of grid rows

This is an upper limit on the number of product granules in an orbit, used internally by the Operational Processor to determine the range of times to be used to derive geolocation tables.

- 1 sl 4 byte(s)
16 disp_tabl
Displacement of table start before ascending node

Because the forward view of the AATSR instrument is displaced by approximately 900 km from the nadir view, the data processing for an orbit must start with instrument scans measured when the satellite is still some 900 km south of the equator, before the ascending node, and the internal look-up tables used by the geolocation algorithm must allow for this. This parameter defines the number of granules prior to the ascending node crossing that must be catered for by the internal tables to permit forward view data on the equator to be geolocated. The current adopted value is 30.

- 1 sl 4 byte(s)
17 ecc_ellip
eccentricity of ellipsoid

The eccentricity of the geodetic reference ellipsoid used for AATSR image geolocation. For the WGS 84 ellipsoid it is 0.0818191908426.

- 1 db 8 byte(s)
18 geo_para
Geodetic parameter (square of ��second eccentricity��)

The square of the geodetic parameter known as the ��second eccentricity�� of the adopted reference ellipsoid. For the WGS 84 ellipsoid it is 0.00673949674227.

- 1 db 8 byte(s)
19 spare_1
Spare
- 1 SpareField 8 byte(s)
20 fst_nad_pix
FIRST_NADIR_PIXEL_NUMBER

Absolute pixel index corresponding to the first element of the internal pixel arrays for nadir view. This index is internal to the Operational Processor; it is not fixed by the actual pixel selection map, and does not impact on the format or scientific contents of the AATSR products.

- 1 sl 4 byte(s)
21 fst_for_pix
FIRST_FORWARD_PIXEL_NUMBER

Absolute pixel index corresponding to the first element of the internal pixel arrays for forward view. This index is internal to the Operational Processor; it is not fixed by the actual pixel selection map, and does not impact on the format or scientific contents of the AATSR products.

- 1 sl 4 byte(s)
22 est_scan_pos_nad
Estimate of relative scan position, nadir scan

The time interval (expressed in days) corresponding to the along track displacement of the nadir instrument scan at the swath edge from the sub-satellite point. (It is, in other words, the linear displacement divided by the satellite velocity.) This parameter is internal to the Operational Processor; it is used to initialise an iteration within the geolocation algorithm, and the output product should be independent of the actual value of this parameter.

days 1 db 8 byte(s)
23 est_scan_pos_for
Estimate of relative scan position, forward scan

The time interval (expressed in days) corresponding to the along track displacement of the nadir instrument scan at the swath edge from the sub-satellite point. (It is, in other words, the linear displacement divided by the satellite velocity.) This parameter is internal to the Operational Processor; it is used to initialise an iteration within the geolocation algorithm, and the output product should be independent of the actual value of this parameter.

days 1 db 8 byte(s)
24 algtrk_ip_int
Along-track interpolation interval

The along-track separation of tie points used internally for geolocation.

- 1 ss 2 byte(s)
25 acrtrk_ip_it
Across-track interpolation interval

The across-track separation of tie points used internally for geolocation

- 1 ss 2 byte(s)
26 eps_x
Regridding perturbation (eps_x)

An across-track tolerance used internally by the regridding algorithm (qv.) The value is set to optimise the efficiency of the regridding algorithm.

m 1 ss 2 byte(s)
27 eps_y
Regridding perturbation (eps_y)

An along-track tolerance used internally by the regridding algorithm (qv.) The value is set to optimise the efficiency of the regridding algorithm.

m 1 ss 2 byte(s)
28 long_off_flag
Longitude offset flag (0=no offset)

This flag is provided for system integration testing, and will be set to zero (off) in normal operational processing.

flag 1 sl 4 byte(s)
29 long_off
Longitude offset (for system testing)

This parameter is an offset applied to the land-sea mask if the longitude offset flag is non-zero. This parameter is provided only for use in system integration testing, and is not relevant to operational product generation.

(1e-6) degrees 1 GeoCoordinate 4 byte(s)
30 spare_2
Spare
- 1 SpareField 8 byte(s)
Record Length : 176

DS_NAME : Characterisation GADS



Format Version 114.0