Description
The cloud and aerosols optical depths at 5km, based on the Level 2 CALIOP 5km layers products. It is an averaging of SODA_AOD products, but discriminated by cloud and aerosol scenes using the CALIOP 05kmClay and 05kmALay scenes classifications.
File Naming Convention
SODA_AOD-5km_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_AOD-5km
| Name | Description | Unit | Type | Fill | Misc |
|---|---|---|---|---|---|
| Latitude | Latitude | deg | float32 | ||
| Longitude | Longitude | deg | float32 | ||
| Time | Time | sec | float64 | ||
| Feature_Classification_Flags_CALIPSO | Feature_Classification_Flags_CALIPSO | NoUnits | uint16 | ||
| Feature_Classification_Flags | Feature_Classification_Flags | NoUnits | uint16 | Scene Identification flag 0 : Invalid 1 : Clear 2 : Cloud 3 : Aerosol 4 : Mixte At this time, nothing can be done to distinguish between Invalid and Clear scenes | |
| Optical_Depth_532_Aerosol | Optical_Depth_532_Aerosol | None | int32 | -32768 | 5km Averaged Optical Depth retrieved from CALIPSO/CLOUDSAT at 532nm for Aerosol Scenes without thin clouds contamination |
| Optical_Depth_532_Cloud | Optical_Depth_532_Cloud | None | int32 | -32768 | 5km Averaged Optical Depth retrieved from CALIPSO/CLOUDSAT at 532nm for Thin Cloud Scenes and mixted scenes thin clouds + aerosols |
| Optical_Depth_1064_Aerosol | Optical_Depth_1064_Aerosol | None | int32 | -32768 | 5km Averaged Optical Depth retrieved from CALIPSO/CLOUDSAT at 1064nm for Aerosol Scenes without thin clouds contamination |
| Optical_Depth_1064_Cloud | Optical_Depth_1064_Cloud | None | int32 | -32768 | 5km Averaged Optical Depth retrieved from CALIPSO/CLOUDSAT at 1064nm for Thin Cloud Scenes and mixted scenes thin clouds + aerosols |
| QA_Flag_Aerosol | QA_Flag_Aerosol | percent | uint8 | 255 | Quality Flag for Aerosol optical depth retrievals : percentage of 333m aerosol scenes averaged at 5km |
| QA_Flag_Cloud | QA_Flag_Cloud | percent | uint8 | 255 | Quality Flag for Cloud optical depth retrievals : percentage of 333m cloud scenes averaged at 5km |
| Scene_Flags | Scene_Flags | None | uint8 | 255 | Flag indicating which algorithm has be used for the aerosol retrieval 0 : Undefined 1 : over ocean, clear sky 2 : over liquid water cloud At this time, only retrievals issued of the ocean algorithm are used |
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
| Product | Download |
|---|---|
| 5km Cloud and Aerosols Optical Depth of Night Orbit starting on Aug. 01 2007 at 00:10:17 UTC | SODA_AOD-5km_v1.0.1_2007-08-01T00-10-17ZN.hdf |
| 5km Cloud and Aerosols Optical Depth of Day Orbit starting on Aug. 01 2007 at 00:10:17 UTC | SODA_AOD-5km_v1.0.1_2007-08-01T00-56-47ZD.hdf |
