Description
The main SODA products are the SODA_AOD which contains the Optical Depth retrievals at 333m, the SODA_AOD-5km with retrievals at 5km classified by cloud or aerosol scenes and the level 3 monthly means. However, several intermediate RADAR/LIDAR intercalibration products are also produced.
SODA_Month-Calibration-Coef
This is the first intermediate SODA product. It contains the monthly based RADAR/LIDAR intercalibration coefficients based on night orbits only
SODA_DN-Recalibration-Coef
It introduces latitudinal calibration correction coefficients for day and night orbits. It manages the variations of the intercalibration along the latitudes.
SODA_AOD
The optical depths retrieved at 333m, based on the Level 1 CALIOP resolution.
File Naming Convention
SODA_Month-Calibration-Coef
SODA_Month-Calibration-Coef_v<Version>_<Year>–<Month>.hdf
SODA_DN-Recalibration-Coef
SODA_DN-Recalibration-Coef_v<Version>_<Year>–<Month>_<Day/Night-Flag>.hdf
SODA_AOD
SODA_AOD_v<Version>_<Orbit-Timestamp>.hdf
| <Version> | A 3 digits dot separated version number as X.X.X |
| <Orbit-Timestamp> | The timestamp of the orbit, using the CALIPSO format YYYY-MM-SSTHH-MM-SSZ[DN] |
| <Year> | The year, on 4 digits |
| <Month> | The month, on 2 digits starting from « 01 » |
| <Day/Night-Flag> | A D or N character that tells if the processed orbits are Day or Night ones |
| <Scenes-ID> | Type of scenes processed. Sc_All means no scenes filtering |
Variables
SODA_Month-Calibration-Coef
| Name | Description | Unit | Type | Fill | Misc |
|---|---|---|---|---|---|
| CPR_Intercalibration_Coefficient | RADAR Intercalibration Coefficient | None | float64 | RADAR to LIDAR Intercalibration coefficient | |
| CALIOP_Intercalibration_Coefficient_532 | LIDAR Intercalibration Coefficient | None | float64 | LIDAR to RADAR Intercalibration coefficient | |
| RADAR_LIDAR_Intercalibration_Coefficient | CPR/CALIOP Intercalibration Coefficients | None | float64 | CPR RADAR/CALIOP LIDAR Intercalibration Coefficients, issued of a polynomial fit |
SODA_DN-Recalibration-Coef
| Name | Description | Unit | Type | Fill | Misc |
|---|---|---|---|---|---|
| CAL532_Lat_Coef | CALIOP 532nm Latitudinal Calibration Correction Coefficient, reference is provided by the CPR | TBD | float64 | Base of CALIOP ocean calibration | |
| CAL1064_Lat_Coef | CALIOP 1064nm Latitudinal Calibration Correction Coefficient, reference is provided by the CPR | TBD | float64 | Base of CALIOP ocean calibration | |
| CAL532_AMSR_Lat_Coef | CALIOP 532nm Latitudinal Calibration Correction Coefficient, reference is provided by AMSR-E | None | float64 | TBD | |
| CAL1064_AMSR_Lat_Coef | CALIOP 1064nm Latitudinal Calibration Correction Coefficient, reference is provided by AMSR-E | None | float64 | TBD | |
| CAL532_1064_Lat_Coef | CALIOP 532nm vs 1064nm color ratio Latitudinal dependencies | None | float64 | TBD | |
| CAL_CPR_Lat_Coef | CPR and AMSR-E Latitudinal relative dependencies | None | float64 | TBD |
SODA_AOD
| Name | Description | Unit | Type | Fill | Misc |
|---|---|---|---|---|---|
| Latitude | Latitude | degrees | float32 | ||
| Longitude | Longitude | degrees | float32 | ||
| TAI_Time | TAI time, using the TAI93 convention | seconds | float64 | Number of seconds since the 1993/01/01 at 00:00:00 | |
| Total_Attenuated_Cross_Section_532 | Total Attenuated Lidar sea surface scatterring cross section at 532nm | sr-1 | float32 | NaN | |
| Attenuated_Cross_Section_1064 | Attenuated Lidar sea surface scatterring cross section at 1064nm | sr-1 | float32 | NaN | |
| Perpendicular_Attenuated_Cross_Section_532 | Perpendicular Attenuated Lidar sea surface scatterring cross section at 532nm | sr-1 | float32 | NaN | |
| CPR_Attenuated_Cross_Section | CPR Attenuated Radar sea surface scatterring cross section | sr-1 | float32 | NaN | |
| AMSR_E_Surface_Wind_Speed | Wind speed 10 meters above the water surface | m.s-1 | float32 | 254.0 | Extracted from RSS AMSR-E Ocean Products. 0 to 250 = valid geophysical data 251 = missing sst or wind speed due to sun glint; missing sst or wind speed near sea ice; missing sst or wind speed due to rain; missing water vapor due to heavy rain; missing sst due to high wind speed (> 20 m/s); missing any due to land proximity 252 = sea ice 253 = observations exist, but are bad (not used in composite maps) 254 = no observations 255 = land mass |
| AMSR_E_Atmospheric_Water_Vapor | Total gaseous water contained in a vertical column of atmosphere | mm | float32 | 254.0 | Extracted from RSS AMSR-E Ocean Products. 0 to 250 = valid geophysical data 251 = missing sst or wind speed due to sun glint; missing sst or wind speed near sea ice; missing sst or wind speed due to rain; missing water vapor due to heavy rain; missing sst due to high wind speed (> 20 m/s); missing any due to land proximity 252 = sea ice 253 = observations exist, but are bad (not used in composite maps) 254 = no observations 255 = land mass |
| AMSR_E_Sea_Surface_Temperature | Temperature of the top layer (skin) of water approximately 1 milimeter thick | Celsius degrees | float32 | 254.0 | Extracted from RSS AMSR-E Ocean Products. 0 to 250 = valid geophysical data 251 = missing sst or wind speed due to sun glint; missing sst or wind speed near sea ice; missing sst or wind speed due to rain; missing water vapor due to heavy rain; missing sst due to high wind speed (> 20 m/s); missing any due to land proximity 252 = sea ice 253 = observations exist, but are bad (not used in composite maps) 254 = no observations 255 = land mass |
| GMAO_Ozone | Ozone number density from GMAO | molecules per cubic meter | float32 | 1.e+15 | Read in CALIOP L1 product |
| GMAO_Pressure | Pressure from GMAO | millibars | float32 | 1.e+15 | Read in CALIOP L1 product |
| GMAO_Temperature | Temperature from GMAO | Celsius degrees | float32 | 1.e+15 | Read in CALIOP L1 product |
| Optical_Depth_CPR_CAL532 | Aerosols Optical Depth over the ocean, retrieved from CPR/CALIOP at 532nm, shot to shot CALIOP resolution retrieval | None | int16 | -32768 | |
| Optical_Depth_CPR_CAL1064 | Aerosols Optical Depth over the ocean, retrieved from CPR/CALIOP at 1064nm, shot to shot CALIOP resolution retrieval | None | int16 | -32768 | |
| Optical_Depth_AMSR_CAL532 | Aerosols Optical Depth over the ocean, retrieved from AMSR-E/CALIOP at 532nm, shot to shot CALIOP resolution retrieval | None | int16 | -32768 | |
| Optical_Depth_AMSR_CAL1064 | Aerosols Optical Depth over the ocean, retrieved from AMSR-E/CALIOP at 1064nm, shot to shot CALIOP resolution retrieval | None | int16 | -32768 | |
| Optical_Depth_MODIS_550 | Aerosols Optical Depth over the ocean, retrieved from MODIS at 550nm, 10 km retrieval interpolated on the shot to shot CALIOP resolution | None | int16 | -32768 | |
| Optical_Depth_MODIS_1064 | Aerosols Optical Depth over the ocean, retrieved from MODIS at 1064nm, 10 km retrieval interpolated on the shot to shot CALIOP resolution | None | int16 | -32768 | |
| Scene_Flags | Scene Description Flags | None | uint8 | 0 | Flags describing how the scene have been selected for inversion. Bits are numbered from right to left using a little endian coding 0 : water bodies 1 : Backscatter centroid is near the surface 2 : Surface signal is under a defined saturation threshold |
| Feature_Classification_Flags | Feature Classification Flags. At this time, only clear sky scenes are identified. | None | uint16 | 0 | Flags describing identified aerosols or cloud features. Bits are numbered from right to left using a little endian coding 0 : clear sky |
| Optical_Depth_QA_Factor | Optical depth retrieval quality assurance factor. NOT SET YET | None | uint8 | 255 | 0->very uncertain ; 100->very confident |
Calibration
Some of the variables are calibrated to an integer format for saving disk space. For every variables, you will find 2 standard SDS attributes called « scale_factor » and « add_offset ». Most of time, the standard HDF formula for scaling raw file values to physical ones is used :
science_value = ( raw_file_value – add_offset ) * scale_factor
Examples
SODA_Month-Calibration-Coef
| Product | Download |
|---|---|
| RADAR/LIDAR Intercalibration Coefficients of Aug. 2007 | SODA_Month-Calibration-Coef_v1.2.3_2007-08.hdf |
SODA_DN-Recalibration-Coef
| Product | Download |
|---|---|
| Night orbits latitudinal recalibration correction of Aug. 2007 | SODA_DN-Recalibration-Coef_v1.2.3_2007-08_N.hdf |
| Day orbits latitudinal recalibration correction of Aug. 2007 | SODA_DN-Recalibration-Coef_v1.2.3_2007-08_D.hdf |
SODA_AOD
| Product | Download |
|---|---|
| 333m Aerosols Optical Depth of Night Orbit starting on Aug. 01 2007 at 00:10:17 UTC | SODA_AOD_v1.2.3_2007-08-01T00-10-17ZN.hdf |
| 333m Aerosols Optical Depth of Day Orbit starting on Aug. 01 2007 at 00:56:47 UTC | SODA_AOD_v1.2.3_2007-08-01T00-56-47ZD.hdf |
