SODA 5km Products

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