Swath Name = "L1B_VIS_Science"
Level = "level1B"
# Footprints = 90
# scanlines per scanset = 3
The names "GeoTrack" and "GeoXTrack" have a special meaning for this document: "Cross-Track" data fields have a hidden dimension of "GeoXTrack"; "Along-Track" data fields have a hidden dimension of "GeoTrack"; "Full Swath Data Fields have hidden dimensions of both "GeoTrack" and "GeoXTrack".
| Name | Value | Explanation |
| GeoXTrack | 90 | Dimension across track for footprint positions. Same as number of footprints per scanline. |
| GeoTrack | # of scan lines in swath | Dimension along track for footprint positions. Same as number of scanlines in granule. (Nominally 45 for Level-2, AMSU, and AIRS/Vis low-rate engineering; 135 for AIRS/Vis and HSB high-rate quantities) |
| SubTrack | 9 | VIS detector elements per AIRS footprint along track (9) |
| SubXTrack | 8 | VIS samples per AIRS footprint across track (8) |
| Bulb | 3 | Number of photometric calibration sources (light bulbs) that can be used as sources for photometric calibration (3) |
| GainHistory | 5 | Number of photometric gain calculations to store for use in smoothing of gain (5) |
| GeoLocationsPerSpot | 4 | Geolocations for the 4 corner pixels in the order: trailing first scanned; trailing last-scanned; leading first-scanned; leading last-scanned. Each footprint also has a central geolocation associated with the swath geolocation lat/lon/time of the footprint. |
| Channel | 4 | Dimension of radiance array |
| Name | Explanation |
| Latitude | Footprint boresight Latitude in degrees North (-90.0 ... 90.0) |
| Longitude | Footprint boresight Longitude in degrees East (-180.0 ... 180.0) |
| Time | Footprint "shutter" TAI Time: floating-point elapsed seconds since Jan 1, 1993 |
| Name | Type | Extra Dimensions | Explanation |
| VegMapDate | string of 8-bit characters | None | UTC-formatted date of vegmap |
| VISDarkAMSUFOVCount | 32-bit integer | None | Number of AMSU-A footprints that are uniformly dark in the level-1B VIS/NIR and are thus likely to be uniformly clear |
| VISBrightAMSUFOVCount | 32-bit integer | None | Number of AMSU-A footprints that are uniformly bright in the level-1B VIS/NIR and are thus likely to be uniformly cloudy |
| processing_level | string of 8-bit characters | None | Zero-terminated character string denoting processing level ("level1B") |
| instrument | string of 8-bit characters | None | Zero-terminated character string denoting instrument ("VIS") |
| DayNightFlag | string of 8-bit characters | None | Zero-terminated character string denoting granule as day and/or night: (Always "Day", "Night", or "Both") |
| AutomaticQAFlag | string of 8-bit characters | None | Zero-terminated character string denoting granule data quality: (Always "Passed", "Failed", or "Suspect") |
| NumTotalData | 32-bit integer | None | Total number of expected data points |
| NumProcessData | 32-bit integer | None | Number of data points which are present and can be processed routinely (state = 0) |
| NumSpecialData | 32-bit integer | None | Number of data points which are present and can be processed only as a special test (state = 1) |
| NumBadData | 32-bit integer | None | Number of data points which are present but cannot be processed (state = 2) |
| NumMissingData | 32-bit integer | None | Number of expected data points which are not present (state = 3) |
| NumLandSurface | 32-bit integer | None | Number of data points for which the surface is more than 90% land |
| NumOceanSurface | 32-bit integer | None | Number of data points for which the surface is less than 10% land |
| node_type | string of 8-bit characters | None | Zero-terminated character string denoting whether granule is ascending, descending, or pole-crossing: ("Ascending" and "Descending" for entirely ascending or entirely descending granules, or "NorthPole" or "SouthPole" for pole-crossing granules) |
| start_year | 32-bit integer | None | Year in which granule started, UTC (e.g. 1999) |
| start_month | 32-bit integer | None | Month in which granule started, UTC (1 ... 12) |
| start_day | 32-bit integer | None | Day of month in which granule started, UTC (1 ... 31) |
| start_hour | 32-bit integer | None | Hour of day in which granule started, UTC (0 ... 23) |
| start_minute | 32-bit integer | None | Minute of hour in which granule started, UTC (0 ... 59) |
| start_sec | 32-bit floating-point | None | Second of minute in which granule started, UTC (0.0 ... 59.0) |
| start_orbit | 32-bit integer | None | Orbit number of mission in which granule started |
| end_orbit | 32-bit integer | None | Orbit number of mission in which granule ended |
| orbit_path | 32-bit integer | None | Orbit path of start orbit (1 ... 233? as defined by EOS project) |
| granule_number | 32-bit integer | None | Number of granule within orbit (1 ... 17?) |
| num_scansets | 32-bit integer | None | Number of scansets in granule (1 ... 45) |
| num_scanlines | 32-bit integer | None | Number of scanlines in granule (3 * num_scansets) |
| start_Latitude | 64-bit floating-point | None | Latitude of spacecraft at start of granule |
| start_Longitude | 64-bit floating-point | None | Longitude of spacecraft at start of granule |
| start_Time | 64-bit floating-point | None | TAI Time at start of granule |
| end_Latitude | 64-bit floating-point | None | Latitude of spacecraft at end of granule |
| end_Longitude | 64-bit floating-point | None | Longitude of spacecraft at end of granule |
| end_Time | 64-bit floating-point | None | TAI Time at end of granule |
| eq_x_longitude | 32-bit floating-point | None | Longitude of spacecraft at southward equator crossing nearest granule start |
| eq_x_tai | 64-bit floating-point | None | Time of eq_x_longitude in TAI units |
| orbitgeoqa | 32-bit integer | None | Orbit Geolocation QA: bit 0 (LSB): bad input value (last scanline); bit 1: bad input value (first scanline); bit 2: PGS_EPH_GetEphMet() returned PGSEPH_E_NO_SC_EPHEM_FILE; bit 3: PGS_EPH_GetEphMet() returned PGSEPH_E_BAD_ARRAY_SIZE; bit 4: PGS_EPH_GetEphMet() returned PGSTD_E_TIME_FMT_ERROR; bit 5: PGS_EPH_GetEphMet() returned PGSTD_E_TIME_VALUE_ERROR; bit 6: PGS_EPH_GetEphMet() returned PGSTD_E_SC_TAG_UNKNOWN; bit 7: PGS_EPH_GetEphMet() returned PGS_E_TOOLKIT; bit 8: PGS_TD_UTCtoTAI() returned PGSTD_E_NO_LEAP_SECS; bit 9: PGS_TD_UTCtoTAI() returned PGSTD_E_TIME_FMT_ERROR; bit 10: PGS_TD_UTCtoTAI() returned PGSTD_E_TIME_VALUE_ERROR; bit 11: PGS_TD_UTCtoTAI() returned PGS_E_TOOLKIT; bit 12: PGS_CSC_DayNight() returned PGSTD_E_NO_LEAP_SECS; bit 13: PGS_CSC_DayNight() returned PGSCSC_E_INVALID_LIMITTAG; bit 14: PGS_CSC_DayNight() returned PGSCSC_E_BAD_ARRAY_SIZE; bit 15: PGS_CSC_DayNight() returned PGSCSC_W_ERROR_IN_DAYNIGHT; bit 16: PGS_CSC_DayNight() returned PGSCSC_W_BAD_TRANSFORM_VALUE; bit 17: PGS_CSC_DayNight() returned PGSCSC_W_BELOW_HORIZON; bit 18: PGS_CSC_DayNight() returned PGSCSC_W_PREDICTED_UT1; bit 19: PGS_CSC_DayNight() returned PGSTD_E_NO_UT1_VALUE; bit 20: PGS_CSC_DayNight() returned PGSTD_E_BAD_INITIAL_TIME; bit 21: PGS_CSC_DayNight() returned PGSCBP_E_TIME_OUT_OF_RANGE; bit 22: PGS_CSC_DayNight() returned PGSCBP_E_UNABLE_TO_OPEN_FILE; bit 22: PGS_CSC_DayNight() returned PGSMEM_E_NO_MEMORY; bit 24: PGS_CSC_DayNight() returned PGS_E_TOOLKIT; bit 25-31: not used |
| num_satgeoqa | 16-bit integer | None | Number of scans with problems in satgeoqa |
| num_glintgeoqa | 16-bit integer | None | Number of scans with problems in glintgeoqa |
| num_moongeoqa | 16-bit integer | None | Number of scans with problems in moongeoqa |
| num_ftptgeoqa | 16-bit integer | None | Number of footprints with problems in ftptgeoqa |
| num_zengeoqa | 16-bit integer | None | Number of footprints with problems in zengeoqa |
| num_demgeoqa | 16-bit integer | None | Number of footprints with problems in demgeoqa |
| num_fpe | 16-bit integer | None | Number of floating point errors |
| LonGranuleCen | 16-bit integer | None | Longitude of the center of the granule in degrees (-180 ... 180) |
| LatGranuleCen | 16-bit integer | None | Latitude of the center of the granule in degrees (-90 ... 90) |
| LocTimeGranuleCen | 16-bit integer | None | Local time at the center of the granule in minutes past midnight (0 ... 1439) |
| limit_scene_counts | Color Counts (see below) | Channel (= 4) * SubTrack (= 9) | Input limit checking on scene data numbers |
| limit_bb_counts | Color Counts (see below) | Channel (= 4) * SubTrack (= 9) | Input limit checking on data numbers from the blackbody (dark target) |
| limit_phot_counts | Color Counts (see below) | Channel (= 4) * SubTrack (= 9) | Input limit checking on data numbers from the photometric calibration source (bright target) |
| limit_vis_det_temp | Color Counts (see below) | None | Input limit checking on Vis sensor array temperature |
| input_scene_counts | Limited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Input statistics on scene data numbers |
| input_bb_counts | Limited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Input statistics on data numbers from the blackbody (dark target) |
| input_phot_counts | Limited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Input statistics on data numbers from the photometric calibration source (bright target) |
| input_vis_det_temp | Limited Engineering Struct (see below) | None | Input statistics on Vis sensor array temperature |
| offset_fit_dev | Fit Deviation (see below) | Channel (= 4) * SubTrack (= 9) | Deviation fit report for offset |
| limit_offsets | Color Counts (see below) | Channel (= 4) * SubTrack (= 9) | Output limit checking on offsets |
| offset_stats | Unlimited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Statistics on offsets |
| offset_unc_stats | Unlimited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Statistics on offset uncertainties |
| gain_scan | 16-bit integer | None | Scanline number of (first) gain calculation completed in granule. 0 for no gain calculation completed in this granule. |
| gain_TAI | 64-bit floating-point | None | TAI time of (first) gain calculation. 0.0 for no gain calculation completed in this granule. |
| gain_TAI_prev | 64-bit floating-point | Bulb (= 3) * GainHistory (= 5) | TAI time of previous valid gain calculation on each bulb. |
| gain_num | 16-bit integer | None | Number of gain calculations in this granule. (Should always be 0 or 1) |
| gain_bulb | 16-bit integer | None | bulb number (1, 2, or 3) of bulb used for (first) gain calculation (including gain claculations started but not completed). 0 for no gain calculation occurred in this granule. |
| bulb_failed | 8-bit integer | None | 1 if a bulb failure was detected in this granule, 0 otherwise. |
| gain | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Gain: number of radiance units per count. (Same as gain_prev on most recently used bulb when no gain calculation was performed in this granule) |
| gain_err | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Error caused by imperfect fit for gain (gain units). (Same as gain_err_prev on most recently used bulb when no gain calculation was performed in this granule) |
| gain_prev | 32-bit floating-point | Bulb (= 3) * GainHistory (= 5) * Channel (= 4) * SubTrack (= 9) | Previous Gain: number of radiance units per count at time of previous gain calculations for each bulb |
| gain_err_prev | 32-bit floating-point | Bulb (= 3) * GainHistory (= 5) * Channel (= 4) * SubTrack (= 9) | gain_err for each gain_prev |
| gain_fit_dev | Fit Deviation (see below) | Channel (= 4) * SubTrack (= 9) | Deviation fit report for gain (invalid if no gain fit) |
| gain_start_TAI | 64-bit floating-point | None | TAI time when photometric calibration source was turned "on" for a gain calculation that had started but had not finished collecting data at the end of the granule. 0.0 for no gain calculation left partial at the end of this granule. |
| gain_num_counts | 32-bit integer | Channel (= 4) * SubTrack (= 9) | The number of data points of counts per detector collected in gain_sum_counts and gain_num_counts2 for a gain calculation that had started but had not finished collecting data at the end of the granule. 0.0 for no gain calculation left partial at the end of this granule. |
| gain_sum_counts | 64-bit floating-point | Channel (= 4) * SubTrack (= 9) | The sum of the counts per detector for a gain calculation that had started but had not finished collecting data at the end of the granule. 0.0 for no gain calculation left partial at the end of this granule. |
| gain_sum_counts2 | 64-bit floating-point | Channel (= 4) * SubTrack (= 9) | The sum of the squares of counts per detector for a gain calculation that had started but had not finished collecting data at the end of the granule. 0.0 for no gain calculation left partial at the end of this granule. |
| primary_bulb | 16-bit integer | None | Bulb number of photometric calibration source used as primary bulb (1, 2, or 3; 0 for no primary bulb) |
| secondary_bulb | 16-bit integer | None | Bulb number of photometric calibration source used as secondary bulb (1, 2, or 3; 0 for no secondary bulb) |
| backup_bulb | 16-bit integer | None | Bulb number of photometric calibration source used as backup bulb (1, 2, or 3; 0 for no backup bulb) |
| K21 | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Gain calculated using bulb 2, divided by gain using bulb 1. (Tracks degradation of bulb 1 relative to bulb 2.) |
| K32 | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Gain calculated using bulb 3, divided by gain using bulb 2. (Tracks degradation of bulb 2 relative to bulb 3.) |
| K31 | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Gain calculated using bulb 3, divided by gain using bulb 1. (Tracks degradation of bulb 1 relative to bulb 3.) |
| K_factors_applied | 8-bit integer | Channel (= 4) | Flag if K factors were applied for each channel (1 for yes, 0 for no) |
| gamma_ground | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Correction factor applied to gain calculation based on observations of known ground targets |
| gamma_MODIS | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Correction factor applied to gain calculation based on co-located MODIS and AIRS observations |
| rad_stats | Unlimited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Statistics on radiances (radiance units) |
| rad_unc_stats | Unlimited Engineering Struct (see below) | Channel (= 4) * SubTrack (= 9) | Statistics on radiance uncertainties due to Noise and offset & gain fit errors (radiance units) |
| granules_present | string of 8-bit characters | None | Zero-terminated character string denoting which adjacent granules were available for smoothing ("All" for both previous & next, "Prev" for previous but not next, "Next" for next but not previous, "None" for neither previous nor next) |
| xtrack_err | 32-bit floating-point | Channel (= 4) | cross-track pixel location error estimate per channel (km) |
| track_err | 32-bit floating-point | Channel (= 4) | Along-track pixel location error estimate per channel (km) |
| align_1_2_nadir | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-nadir AIRS footprints (45 & 46) between VIS channels 1 & 2 |
| align_2_3_nadir | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-nadir AIRS footprints (45 & 46) between VIS channels 2 & 3 |
| align_2_4_nadir | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-nadir AIRS footprints (45 & 46) between VIS channels 2 & 4 |
| align_1_2_maxang | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-limb AIRS footprints (1 & 90) between VIS channels 1 & 2 |
| align_2_3_maxang | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-limb AIRS footprints (1 & 90) between VIS channels 2 & 3 |
| align_2_4_maxang | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-limb AIRS footprints (1 & 90) between VIS channels 2 & 4 |
| align_vis_airs | 32-bit floating-point | None | Expected error (km) between the pixel locations for the corner locations of near-nadir AIRS footprints (45 & 46) between the AIRS center and all VIS channels |
| Name | Type | Extra Dimensions | Explanation |
| offset | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Offset: number of counts expected for no radiance at time nadirTAI |
| offset_err | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Error caused by imperfect fit for offset (radiance units) |
| NeN | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Noise-equivalent Radiance (radiance units) |
| rad_unc | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) | Radiance uncertainty detected from goodness-of-fit in calibration. Excludes noise (reported in NeN) and biases. (radiance units) |
| satheight | 32-bit floating-point | None | Satellite altitude at nadirTAI in km above reference ellipsoid (e.g. 725.2) |
| satroll | 32-bit floating-point | None | Satellite attitude roll angle at nadirTAI (-180.0 ... 180.0 angle about the +x (roll) ORB axis, +x axis is positively oriented in the direction of orbital flight completing an orthogonal triad with y and z.) |
| satpitch | 32-bit floating-point | None | Satellite attitude pitch angle at nadirTAI (-180.0 ... 180.0 angle about +y (pitch) ORB axis. +y axis is oriented normal to the orbit plane with the positive sense opposite to that of the orbit's angular momentum vector H.) |
| satyaw | 32-bit floating-point | None | Satellite attitude yaw angle at nadirTAI (-180.0 ... 180.0 angle about +z (yaw) axis. +z axis is positively oriented earthward parallel to the satellite radius vector R from the spacecraft center of mass to the center of the Earth.) |
| satgeoqa | 32-bit integer | None | Satellite Geolocation QA flags: bit 0 (LSB): bad input value; bit 1: PGS_TD_TAItoUTC() returned PGSTD_E_NO_LEAP_SECS; bit 2: PGS_TD_TAItoUTC() returned PGS_E_TOOLKIT; bit 3: PGS_EPH_EphemAttit() returned PGSEPH_W_BAD_EPHEM_VALUE; bit 4: PGS_EPH_EphemAttit() returned PGSEPH_E_BAD_EPHEM_FILE_HDR; bit 5: PGS_EPH_EphemAttit() returned PGSEPH_E_NO_SC_EPHEM_FILE; bit 6: PGS_EPH_EphemAttit() returned PGSEPH_E_NO_DATA_REQUESTED; bit 7: PGS_EPH_EphemAttit() returned PGSTD_E_SC_TAG_UNKNOWN; bit 8: PGS_EPH_EphemAttit() returned PGSEPH_E_BAD_ARRAY_SIZE; bit 9: PGS_EPH_EphemAttit() returned PGSTD_E_TIME_FMT_ERROR; bit 10: PGS_EPH_EphemAttit() returned PGSTD_E_TIME_VALUE_ERROR; bit 11: PGS_EPH_EphemAttit() returned PGSTD_E_NO_LEAP_SECS; bit 12: PGS_EPH_EphemAttit() returned PGS_E_TOOLKIT; bit 13: PGS_CSC_ECItoECR() returned PGSCSC_W_BAD_TRANSFORM_VALUE; bit 14: PGS_CSC_ECItoECR() returned PGSCSC_E_BAD_ARRAY_SIZE; bit 15: PGS_CSC_ECItoECR() returned PGSTD_E_NO_LEAP_SECS; bit 16: PGS_CSC_ECItoECR() returned PGSTD_E_TIME_FMT_ERROR; bit 17: PGS_CSC_ECItoECR() returned PGSTD_E_TIME_VALUE_ERROR; bit 18: PGS_CSC_ECItoECR() returned PGSCSC_W_PREDICTED_UT1; bit 19: PGS_CSC_ECItoECR() returned PGSTD_E_NO_UT1_VALUE; bit 20: PGS_CSC_ECItoECR() returned PGS_E_TOOLKIT; bit 21: PGS_CSC_ECRtoGEO() returned PGSCSC_W_TOO_MANY_ITERS; bit 22: PGS_CSC_ECRtoGEO() returned PGSCSC_W_INVALID_ALTITUDE; bit 23: PGS_CSC_ECRtoGEO() returned PGSCSC_W_SPHERE_BODY; bit 24: PGS_CSC_ECRtoGEO() returned PGSCSC_W_LARGE_FLATTENING; bit 25: PGS_CSC_ECRtoGEO() returned PGSCSC_W_DEFAULT_EARTH_MODEL; bit 26: PGS_CSC_ECRtoGEO() returned PGSCSC_E_BAD_EARTH_MODEL; bit 27: PGS_CSC_ECRtoGEO() returned PGS_E_TOOLKIT; bit 28-31: not used |
| glintgeoqa | 16-bit integer | None | Glint Geolocation QA flags: bit 0 (LSB): bad input value; bit 1: PGS_CBP_Earth_CB_Vector() returned PGSCBP_W_EARTH_CB_ID; bit 2: PGS_CBP_Earth_CB_Vector() returned PGSCBP_E_INVALID_CB_ID; bit 3: PGS_CBP_Earth_CB_Vector() returned PGSTD_E_BAD_INITIAL_TIME; bit 4: PGS_CBP_Earth_CB_Vector() returned PGSCBP_E_BAD_ARRAY_SIZE; bit 5: PGS_CBP_Earth_CB_Vector() returned PGSCBP_E_UNABLE_TO_OPEN_FILE; bit 6: PGS_CBP_Earth_CB_Vector() returned PGSCBP_E_TIME_OUT_OF_RANGE; bit 7: PGS_CBP_Earth_CB_Vector() returned PGSTD_E_NO_LEAP_SECS; bit 8: PGS_CBP_Earth_CB_Vector() returned PGSCBP_W_BAD_CB_VECTOR; bit 9: PGS_CBP_Earth_CB_Vector() returned PGS_E_TOOLKIT; bit 10: PGS_CSC_ECItoECR() returned any 'W' class return code (for Glint); bit 11: PGS_CSC_ECItoECR() returned any 'E' class return code (for Glint); bit 12: PGS_CSC_ECRtoGEO() returned any 'W' class return code (for Glint); bit 13: PGS_CSC_ECRtoGEO() returned any 'E' class return code (for Glint); bit 14: PGS_CSC_ECItoECR() returned any 'W' class return code (for Sun); bit 15: PGS_CSC_ECItoECR() returned any 'E' class return code (for Sun) |
| moongeoqa | 16-bit integer | None | Moon Geolocation QA flags: bit 0: bad input value; bit 1: PGS_TD_TAItoUTC() returned PGSTD_E_NO_LEAP_SECS; bit 2: PGS_TD_TAItoUTC() returned PGS_E_TOOLKIT; bit 3: PGS_CBP_Sat_CB_Vector() returned PGSCSC_W_BELOW_SURFACE; bit 4: PGS_CBP_Sat_CB_Vector() returned PGSCBP_W_BAD_CB_VECTOR; bit 5: PGS_CBP_Sat_CB_Vector() returned PGSCBP_E_BAD_ARRAY_SIZE; bit 6: PGS_CBP_Sat_CB_Vector() returned PGSCBP_E_INVALID_CB_ID; bit 7: PGS_CBP_Sat_CB_Vector() returned PGSMEM_E_NO_MEMORY; bit 8: PGS_CBP_Sat_CB_Vector() returned PGSCBP_E_UNABLE_TO_OPEN_FILE; bit 9: PGS_CBP_Sat_CB_Vector() returned PGSTD_E_BAD_INITIAL_TIME; bit 10: PGS_CBP_Sat_CB_Vector() returned PGSCBP_E_TIME_OUT_OF_RANGE; bit 11: PGS_CBP_Sat_CB_Vector() returned PGSTD_E_SC_TAG_UNKNOWN; bit 12: PGS_CBP_Sat_CB_Vector() returned PGSEPH_E_BAD_EPHEM_FILE_HDR; bit 13: PGS_CBP_Sat_CB_Vector() returned PGSEPH_E_NO_SC_EPHEM_FILE; bit 14: PGS_CBP_Sat_CB_Vector() returned PGS_E_TOOLKIT; bit 15: not used |
| nadirTAI | 64-bit floating-point | None | TAI time at which instrument is nominally looking directly down. (between footprints 15 & 16 for AMSU or between footprints 45 & 46 for AIRS/Vis & HSB) |
| sat_lat | 64-bit floating-point | None | Satellite latitude in degrees (-90.0 ... 90.0) |
| sat_lon | 64-bit floating-point | None | Satellite longitude in degrees (-180.0 ... 180.0) |
| scan_node_type | 8-bit integer | None | 'A' for ascending, 'D' for descending, 'N' for North-Polar, 'S' for South-Polar |
| glintlat | 32-bit floating-point | None | Solar glint latitude in degrees at nadirTAI (-90.0 ... 90.0) |
| glintlon | 32-bit floating-point | None | Solar glint longitude in degrees at nadirTAI (-180.0 ... 180.0) |
| ViSnsrArrTemp | 32-bit floating-point | None | Vis/NIR Sensor Array Temperature (Celcius) |
| ScHeadTemp1 | 32-bit floating-point | None | Scanner Head Housing Temperature 1 (active A or B) (Celcius) |
| OpMode | 16-bit integer | None | Instrument Operations Mode. See AIRS Command Handbook, section 7.2.4, for a definition of each bit. |
| Name | Type | Extra Dimensions | Explanation |
| radiances | 32-bit floating-point | Channel (= 4) * SubTrack (= 9) * SubXTrack (= 8) | Radiances for each channel in Watts/m**2/micron/steradian (Channel 1: ~0.40 micron; Ch 2: ~0.6 micron; Ch 3: ~0.8 micron; Ch 4: broadband) |
| ref_scaled_veg_index | string of 8-bit characters | SubTrack (= 9) * SubXTrack (= 8) | The AIRS Veg. Index value is defined as (Ch3 - Ch2) / (Ch3 + Ch2), where ChX is the reflectivity observed in channel x. The scaled Veg. Index value is a one-byte, unsigned integer representation of NDVI: scaledNDVI = NDVI*100 + 100. In addition, there are four special scaled values used as flags: 0 => Bright Desert pixel (assigned manually); 1 => Ocean (preserved from original 1 km AVHRR maps); 2 => Interrupted area (preserved from original 1 km AVHRR maps); 3 => Missing data. |
| bright_index | 16-bit integer | None | Brightness index (0...5, 5 is brightest. -9999 for not calculated |
| inhomo_index | 16-bit integer | None | Inhomgeneity index (0...64, Meaning TBS, -9999 for not calculated |
| scanang | 32-bit floating-point | None | Scanning angle of AIRS instrument for this footprint (-180.0 ... 180.0) |
| ftptgeoqa | 32-bit integer | None | Footprint Geolocation QA flags: bit 0 (LSB): bad input value; bit 1: PGS_TD_TAItoUTC() returned PGSTD_E_NO_LEAP_SECS; bit 2: PGS_TD_TAItoUTC() returned PGS_E_TOOLKIT; bit 3: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_MISS_EARTH; bit 4: PGS_CSC_GetFOV_Pixel() returned PGSTD_E_SC_TAG_UNKNOWN; bit 5: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_ZERO_PIXEL_VECTOR; bit 6: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_BAD_EPH_FOR_PIXEL; bit 7: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_INSTRUMENT_OFF_BOARD; bit 8: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_BAD_ACCURACY_FLAG; bit 9: PGS_CSC_GetFOV_Pixel() returned PGSCSC_E_BAD_ARRAY_SIZE; bit 10: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_DEFAULT_EARTH_MODEL; bit 11: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_DATA_FILE_MISSING; bit 12: PGS_CSC_GetFOV_Pixel() returned PGSCSC_E_NEG_OR_ZERO_RAD; bit 13: PGS_CSC_GetFOV_Pixel() returned PGSMEM_E_NO_MEMORY; bit 14: PGS_CSC_GetFOV_Pixel() returned PGSTD_E_NO_LEAP_SECS; bit 15: PGS_CSC_GetFOV_Pixel() returned PGSTD_E_TIME_FMT_ERROR; bit 16: PGS_CSC_GetFOV_Pixel() returned PGSTD_E_TIME_VALUE_ERROR; bit 17: PGS_CSC_GetFOV_Pixel() returned PGSCSC_W_PREDICTED_UT1; bit 18: PGS_CSC_GetFOV_Pixel() returned PGSTD_E_NO_UT1_VALUE; bit 19: PGS_CSC_GetFOV_Pixel() returned PGS_E_TOOLKIT; bit 20: PGS_CSC_GetFOV_Pixel() returned PGSEPH_E_BAD_EPHEM_FILE_HDR; bit 21: PGS_CSC_GetFOV_Pixel() returned PGSEPH_E_NO_SC_EPHEM_FILE; bit 22-31: not used |
| zengeoqa | 16-bit integer | None | Satellite zenith Geolocation QA flags: bit 0 (LSB): (Spacecraft) bad input value; bit 1: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_W_BELOW_HORIZON; bit 2: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_W_UNDEFINED_AZIMUTH; bit 3: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_W_NO_REFRACTION; bit 4: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_E_INVALID_VECTAG; bit 5: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_E_LOOK_PT_ALTIT_RANGE; bit 6: PGS_CSC_ZenithAzimuth(S/C) returned PGSCSC_E_ZERO_INPUT_VECTOR; bit 7: PGS_CSC_ZenithAzimuth(S/C) returned PGS_E_TOOLKIT; bit 8: (Sun) bad input value; bit 9: (suppressed) PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_W_BELOW_HORIZON (This is not an error condition - the sun is below the horizon at night); bit 10: PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_W_UNDEFINED_AZIMUTH; bit 11: PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_W_NO_REFRACTION; bit 12: PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_E_INVALID_VECTAG; bit 13: PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_E_LOOK_PT_ALTIT_RANGE; bit 14: PGS_CSC_ZenithAzimuth(Sun) returned PGSCSC_E_ZERO_INPUT_VECTOR; bit 15: PGS_CSC_ZenithAzimuth(Sun) returned PGS_E_TOOLKIT |
| demgeoqa | 16-bit integer | None | Digital Elevation Model (DEM) Geolocation QA flags: bit 0 (LSB): bad input value; bit 1: Could not allocate memory; bit 2: Too close to North or South pole. Excluded; bit 3: Layer resolution incompatibility. Excluded; bit 4: Any DEM Routine (elev) returned PGSDEM_E_IMPROPER_TAG; bit 5: Any DEM Routine (elev) returned PGSDEM_E_CANNOT_ACCESS_DATA; bit 6: Any DEM Routine (land/water) returned PGSDEM_E_IMPROPER_TAG; bit 7: Any DEM Routine (land/water) returned PGSDEM_E_CANNOT_ACCESS_DATA; bit 8: Reserved for future layers; bit 9: Reserved for future layers; bit 10: PGS_DEM_GetRegion(elev) returned PGSDEM_M_FILLVALUE_INCLUDED; bit 11: PGS_DEM_GetRegion(land/water) returned PGSDEM_M_FILLVALUE_INCLUDED; bit 12: Reserved for future layers; bit 13: PGS_DEM_GetRegion(all) returned PGSDEM_M_MULTIPLE_RESOLUTIONS; bit 14: PGS_CSC_GetFOV_Pixel() returned any 'W' class return code; bit 15: PGS_CSC_GetFOV_Pixel() returned any 'E' class return code |
| satzen | 32-bit floating-point | None | Spacecraft zenith angle (0.0 ... 180.0 degrees from zenith GEO) |
| satazi | 32-bit floating-point | None | Spacecraft azimuth angle (-180.0 ... 180.0 degrees E of N GEO) |
| solzen | 32-bit floating-point | None | Solar zenith angle (0.0 ... 180.0 degrees from zenith GEO) |
| solazi | 32-bit floating-point | None | Solar azimuth angle (-180.0 ... 180.0 degrees E of N GEO) |
| sun_glint_distance | 16-bit integer | None | Distance (km) from footprint center to location of the sun glint |
| topog | 32-bit floating-point | None | Mean topography in meters above reference ellipsoid |
| topog_err | 32-bit floating-point | None | Error estimate for topog |
| landFrac | 32-bit floating-point | None | Fraction of spot that is land (0.0 ... 1.0) |
| landFrac_err | 32-bit floating-point | None | Error estimate for landFrac |
| state | 32-bit integer | None | Data state: 0:Process, 1:Special, 2:Erroneous, 3:Missing |
| cornerlats | 32-bit floating-point | GeoLocationsPerSpot (= 4) * Channel (= 4) | Latitudes at the centers of the pixels at the corners of the IR footprint by channel |
| cornerlons | 32-bit floating-point | GeoLocationsPerSpot (= 4) * Channel (= 4) | Longitudes at the centers of the pixels at the corners of the IR footprint by channel |
Limited Engineering Struct: This type is used for engineering data fields for which there are known "yellow" limits
| Field Name | Type | Explanation |
| min | 32-bit floating-point | Minimum value field takes on in granule (not valid when num_in = 0) |
| max | 32-bit floating-point | Maximum value field takes on in granule (not valid when num_in = 0) |
| mean | 32-bit floating-point | Mean of in-range values field takes on in granule (not valid when num_in = 0) |
| dev | 32-bit floating-point | Standard Deviation of in-range values field takes on in granule (not valid when num_in = 0) |
| num_in | 32-bit integer | Count of in-range values field takes on in granule |
| num_lo | 32-bit integer | Count of out-of-range low values field takes on in granule |
| num_hi | 32-bit integer | Count of out-of-range high values field takes on in granule |
| num_bad | 32-bit integer | Count of occassions on which field takes on invalid flag value (-9999) in granule |
| range_min | 32-bit floating-point | Minimum in-range value. Any value less than this is counted in num_lo and is not used in the calculation of mean & dev. |
| range_max | 32-bit floating-point | Maximum in-range value. Any value greater than this is counted in num_hi and is not used in the calculation of mean & dev. |
| missing | 8-bit integer | Missing limits flags. Bit 0 (LSB) is 1 when yellow low (range_min) limit is missing; Bit 1 is high when yellow high (range_max) limit is missing; other bits unused, set to 0. |
| max_track | 32-bit integer | GeoTrack index (counting from 1) where max was found |
| max_xtrack | 32-bit integer | GeoXTrack index (counting from 1) where max was found |
| min_track | 32-bit integer | GeoTrack index (counting from 1) where min was found |
| min_xtrack | 32-bit integer | GeoXTrack index (counting from 1) where min was found |
Unlimited Engineering Struct: This type is used for engineering data fields for which there are NOT known "yellow" limits
| Field Name | Type | Explanation |
| min | 32-bit floating-point | Minimum value field takes on in granule (not valid when num = 0) |
| max | 32-bit floating-point | Maximum value field takes on in granule (not valid when num = 0) |
| mean | 32-bit floating-point | Mean of values field takes on in granule (not valid when num = 0) |
| dev | 32-bit floating-point | Standard Deviation of values field takes on in granule (not valid when num = 0) |
| num | 32-bit integer | Count of occurrences of field in granule (not including those counted in num_bad) |
| num_bad | 32-bit integer | Count of occassions on which field takes on invalid flag value (-9999) in granule |
| max_track | 32-bit integer | GeoTrack index (counting from 1) where max was found |
| max_xtrack | 32-bit integer | GeoXTrack index (counting from 1) where max was found |
| min_track | 32-bit integer | GeoTrack index (counting from 1) where min was found |
| min_xtrack | 32-bit integer | GeoXTrack index (counting from 1) where min was found |
Color Counts: This type tracks counts of values received during an interval by how they compare to corresponding "red" and "yellow" limits
| Field Name | Type | Explanation |
| red_lo_limit | 32-bit floating-point | Value of the low "red" limit. |
| red_lo_cnt | 16-bit integer | Count of values less than the low "red" limit. This is an "Alarm" condition. |
| to_red_lo | 16-bit integer | Count of occasions on which the "color" of this field changed from some other value to "red_low". |
| yellow_lo_limit | 32-bit floating-point | Value of the low "yellow" limit. |
| yellow_lo_cnt | 16-bit integer | Count of values greater than the low "red" limit but less than the low "yellow" limit. This is a "Warning" condition. |
| to_yellow_lo | 16-bit integer | Count of occasions on which the "color" of this field changed from some other value to "yellow_low". |
| green_cnt | 16-bit integer | Count of values greater than the low "yellow" limit but less than the high "yellow" limit. |
| to_green | 16-bit integer | Count of occasions on which the "color" of this field changed from some other value to "green". |
| yellow_hi_limit | 32-bit floating-point | Value of the high "yellow" limit. |
| yellow_hi_cnt | 16-bit integer | Count of values greater than the high "yellow" limit but less than the high "red" limit. This is a "Warning" condition. |
| to_yellow_hi | 16-bit integer | Count of occasions on which the "color" of this field changed from some other value to "yellow_high". |
| red_hi_limit | 32-bit floating-point | Value of the high "red" limit. |
| red_hi_cnt | 16-bit integer | Count of values greater than the high "red" limit. This is an "Alarm" condition. |
| to_red_hi | 16-bit integer | Count of occasions on which the "color" of this field changed from some other value to "red_high". |
| missing | 8-bit integer | Missing limits flags. Bit 0 (LSB) is 1 when yellow low limit (yellow_lo_limit) is missing; Bit 1 is high when yellow high limit is missing; Bit 2 is 1 when red low limit is missing; Bit 3 is 1 when red high limit is missing; Other bits unused set to 0. |
Fit Deviation: This type provides details about the greatest deviation of input from a fit
| Field Name | Type | Explanation |
| fit_scanline | 8-bit integer | Scanline for which fit is being performed. (1..135 for case of AIRS with 45 scansets of 3 scanlines) |
| dev_granule | 8-bit integer | Granule in which maximum deviation from fit is found. (-1 for previous granule; 0 for current granule; 1 for next) |
| dev_scanline | 8-bit integer | Scanline in which maximum deviation from fit is found. |
| dev | 32-bit floating-point | magnitude of maximum fit in units of "y" (negative for raw data point less than calculated fit) |