The POLDER/PARASOL Products

    Latest status update

    Information regarding POLDER/PARASOL reprocessing and synergy with observations from other sensors may be found in the News and events section:
    • Release of PARASOL-MODIS unique synergy products – April 2016
    • All PARASOL data records now available in HDF format – March 2016
    • Full reprocessing of PARASOL data archive with new data sets available – September 2015, update September 2016
    • PARASOL Level-1 and Level-2-and-up Data Reprocessing Completion – June 2015

    Level-1 products (Satellite measurements)

    Level-0 to Level-1 POLDER/PARASOL processing is performed by CNES. This so-called "Level-1 processing" includes calibration, radiometric and geometric processing. CNES completed the final Level-1 reprocessing in 2014, using an improved algorithm incorporating all final in-flight radio/metric calibration parameters (CNES document PARASOL_L1_final_reprocessing.pdf ).
    The Level-1 products consist of normalized top-of-the-atmosphere radiance for each channel along with geolocation, time of acquisition, and other relevant parameters and flags. All parameters are given at a spatial resolution close to 6 km x 6 km at nadir and are given on a pixel basis in binary format for each orbit (14 or 15 a day).

    CNES issued a document about POLDER and PARASOL level-1 product data format and user manual (POLDER_Level-1_format.pdf , PARASOL_Level-1_format.pdf).

    A subset of the PARASOL Level-1 radiances colocated with CALIPSO/CALIOP is available in the CALIOP CALTRACK product suite. The CALTRACK products subset the original products from many sensors at the CALIOP subtrack i.e. they provide all available data temporally and spatially colocated with the LIDAR measurements.

    POLDER/PARASOL Level-1 products
    Retrieved parameter Product Name Format Spatial
    Resolution
    Temporal
    Coverage
    Time period
    Level-1 POLDER/PARASOL normalized radiances (directional) Resp.: CNES
    Normalized radiance
    Second component of Stokes Vector (Q)
    Third component of Stokes Vector (U)
    L1_B redirection to documentation Binary and
    HDF5
    Full resolution
    (about 6. km,
    nadir pixel size)
    1 file/orbit March 2005 -
    Oct. 2013
    Level-1 PARASOL normalized radiance at CALIPSO/CALIOP subtrack Resp.: LOA
    Normalized radiance
    Second component of Stokes Vector (Q)
    Third component of Stokes Vector (U)
    CALTRACK-333m_
    PAR-L1B redirection to documentation
    HDF5 333 m sampling
    (usually 2 per
    orbit)
    1 file per
    CALIOP file
    June 2006 -
    Oct. 2013

    Level-2 and Level-3 products (Geophysical parameters)

    There are two thematic POLDER/PARASOL scientific product suites: "Earth Radiation Budget, Water Vapor and Clouds" and "Aerosols". They are generated from the Level-1 data alone or in combination with other data sets, using science codes developed by the French science team at LOA.
    Products derived from PARASOL data alone include the Level-2 standard data sets (of orbit type), the global Level-3 (monthly and/or decadal), the global Level-3 gridded atmospheric data sets (daily and monthly), and the PARASOL "CALTRACK" products subsets at the CALIPSO/CALIOP subtrack. More recently, an innovative algorithm, called "GRASP" (Generalized Retrieval of Aerosol and Surface Properties), has been developed to retrieve simultaneously many more parameters compared to a standard product.
    One unique synergistic Level-2 product is derived using the combination of PARASOL and Aqua/MODIS observations ("PM-L2").

    • The Level-2 products are derived from individual Level-1 products. All parameters are given at a spatial resolution close to 18.5 kmx18.5 km (1/6 deg. x 1/6 deg., i.e. 3x3 pixels of the Level-1 grid) for each orbit. The parameters are given on a pixel basis in binary format. (POLDER/PARASOL_Level-2_format.pdf )
    • The global Level-3 products are generated from the Level-2 products. All parameters are given at 1/6 deg. spatial resolution globally on a pixel basis and in binary format. The aerosol products (land and ocean) include both decadal (i.e. 10-day) and monthly composites and the cloud and radiation products include monthly composites. (POLDER/PARASOL_Level-3_format.pdf)
    • The global Level-3 gridded atmospheric products include selected parameters either from the Level-2 data sets (for the daily synthesis) or from the Level-3 (for the monthly synthesis). The selected parameters are reprojected in a Plate-Carrée (i.e. equi-rectangular) projection grid at 1/6 deg. resolution in HDF-EOS format. (POLDER/PARASOL Gridded Atmosphere Product)
    • Combination of PARASOL-MODIS data leads to new global Level-2 aerosol and cloud parameters such as the quantization of aerosol plumes over cloud layers or the macro-physical properties and thermodynamic phase of clouds. The parameters are given on an equi-rectangular projection grid at 1/6 deg. spatial resolution in HDF format.
    • Subset of PARASOL Level-2 aerosol and cloud parameters at CALIOP subtrack at 5-km spatial resolution (CALTRACK).
    • A new algorithm leads to new global daily and monthly Level-3 aerosol products at 1/18 deg. x 1/18 deg. spatial resolution (GRASP).

    The tables provide the list of the scientific product parameters and links to the product documentation and illustration (for Level-3).

    POLDER/PARASOL Level-2 science products
    Retrieved parameter Product Name Format Spatial
    Resolution
    Temporal
    Coverage
    Time period
    Level-2 Aerosol over ocean Resp.: LOA
    Aerosol optical thickness (AOT)
    Uncertainty of AOT
    Angstrom exponent
    Effective radius
    backscattering coefficient
    Non-sphericity index
    OC2 Binary and
    HDF5
    1/6 deg 1 file/orbit March 2005 -
    Oct. 2013
    Level-2 Aerosol over land Resp.: LOA
    Aerosol optical thickness
    Angstrom exponent
    Aerosol altitude
    LS2 Binary and
    HDF5
    1/6 deg 1 file/orbit March 2005 -
    Oct. 2013
    Level-2 Earth radiative budget, Water vapor and clouds Resp.: LOA
    Shortwave broadband albedo
    Visible narrowband albedo
    Cloud fraction
    Cloud albedo
    Cloud thermodynamic phase
    Cloud optical thickness
    Cloud oxygen pressure
    Cloud Rayleigh pressure
    Cloud top oxygen pressure
    Cloud middle oxygen pressure
    Cloud geometrical extent
    Water vapor integrated content
    RB2 Binary and
    HDF5
    1/6 deg 1 file/orbit March 2005 -
    Oct. 2013
    Level-2 Aerosol and cloud products from combined PARASOL-MODIS Resp.: LOA
    Cloud classification
    Cloud thermodynamic phase
    Cloud top pressure
    Cloud geometrical thickness
    Aerosol optical thickness above
    cloud layers
    PM-L2 Binary and
    HDF5
    Clouds:
    Full resolution
    Aerosols:
    1/6 deg
    1 file/orbit March 2005 -
    Oct. 2013
    Restricted access
    Level-2 PARASOL aerosol and cloud parameters at CALIPSO/CALIOP subtrack Resp.: LOA
    Aerosol parameters over ocean

    Aerosol parameters over land

    Radiative budget, water vapor
    and clouds parameters

    Cloud, aerosol above cloud
    layers
    CALTRACK-5km_
    PAR-OC2 redirection to documentation
    CALTRACK-5km_
    PAR-LS2 redirection to documentation
    CALTRACK-5km_
    PAR-RB2 redirection to documentation
    CALTRACK-5km_
    PM-L2 redirection to documentation
    HDF5 5 km sampling 1 file per
    CALIOP file
    June 2006 -
    Oct. 2013
    CALTRACK PM-L2 in
    restricted access


    POLDER/PARASOL Level-3 science products
    Retrieved parameter Product Name Format Spatial
    Resolution
    Composite
    Period
    Time period
    Level-3 Monthly aerosol over ocean Resp.: LOA
    Statistics computed from OC2 (L2 aerosol
    over ocean) parameters
    OC3 Binary and
    HDF5
    1/6 deg.
    (3x3 pixels
    Decadal
    Monthly
    March 2005-Oct. 2013
    Level-3 Monthly aerosol over land Resp.: LOA
    Statistics computed from LS2 (L2 aerosol
    over land) parameters
    AC3 Binary and
    HDF5
    1/6 deg.
    (3x3 pixels)
    Decadal
    Monthly
    March 2005-Oct. 2013
    Level-3 Monthly Earth radiative budget, Water vapor and clouds Resp.: LOA
    Statistics computed from RB2 (L2 radiative
    and cloud) parameters
    RB3 Binary and
    HDF5
    1/6 deg.
    (3x3 pixels)
    Monthly March 2005-Oct. 2013
    Level-3 Daily Global gridded atmosphere products Resp.: LOA
    Aerosol parameters
    (optical thickness, Angstrom exponent...)
    Cloud parameters
    (optical thickness, cloud cover, phase...)
    Water vapor content
    Shortwave flux...
    PR_ATM_D Binary and
    HDF4
    1/6 deg.
    (3x3 pixels)
    Monthly March 2005-Oct. 2013
    Level-3 Monthly Global gridded atmosphere products Resp.: LOA
    Aerosol parameters
    (optical thickness, Angstrom exponent...)
    Cloud parameters
    (optical thickness, cloud cover, phase...)
    Water vapor content
    Shortwave flux...
    PR_ATM_M Binary and
    HDF4
    1/6 deg.
    (3x3 pixels)
    Monthly March 2005-Oct. 2013
    Level-3 Daily global aerosol and surface parameters Resp.: LOA
    Aerosol parameters
    Surface parameters
    GRASP redirection to documentation HDF5 1/18 deg.
    about 6 km
    Daily March 2006 -
    Oct. 2013

    POLDER/PARASOL processing scheme

    These diagrams show the POLDER/PARASOL processing and data flow from Level-0 through Level-3 for Aerosol products over ocean (OC2 and OC3) and over land (LS2 and AC3), Land surface products (LS3), radiative budget, water vapor and cloud products (RB2 and RB3) (left diagram), and global gridded atmosphere products (PR_ATM) (right diagram). Click on the image for a larger view. Details on products are provided in Tables below.
    Links to the detailed description of the aerosol algorithm and RB, WV and cloud algorithm