V2.2 L2AS Detailed Release Description
April 15, 2002

Algorithm Changes

  • Implement new 'optically thick atmosphere' algorithm.
  • Implement new experimental aerosol retrieval algorithm over homogeneous surface types.
  • Change selection criteria for input equivalent reflectances to be used in aerosol retrievals over heterogeneous surfaces.
  • Change selection criteria for choosing to perform an aerosol retrieval over dark water.
  • Change optical depth default which uses optical depth upper bound: instead of default = upper bound - 0.05, use default = upper bound * 0.9.
  • Update calculation of old NumClearCam field (compute number of clear cameras) to calculation of new NumCamUsed field (compute number of cameras used in retrieval).

Bug Fixes

  • Report previously-computed data fields in product even when subsequent processing encounters an error.
  • Clean up memory-related errors.
  • Add correction for delta function problem in diffuse atmospheric transmittance terms.

Aerosol Product Changes

  • Change field name AerCompModId to AerRetrSuccFlagPerMixture
  • Change field name NumSuccAerModel to NumSuccAerMixture
  • Change field name NumClearCam to NumCamUsed
  • Change field name HetLandContrast to HetContrast
  • Change field name ColOptDepth to OptDepthPerMixture
  • Change field name ColOptDepthUnc to OptDepthUncPerMixture
  • Change field name ChisqHetSpectral to ChisqHetCalcPerBand
  • Change the following field names and add a band dimension:
    RegMeanOptDepth to RegMeanSpectralOptDepth
    RegMedianOptDepth to RegMedianSpectralOptDepth
    RegStDevOptDepth to RegStDevSpectralOptDepth
    RegWgtdMeanOptDepth to RegWgtdMeanSpectralOptDepth
    RegWgtdStDevOptDepth to RegWgtdStDevSpectralOptDepth
    BestFitOptDepth to RegBestFitSpectralOptDepth
  • Change the following field names:
    BestFitChisq to RegBestFitChisq
    BestFitMixture to RegBestFitMixture
    SfcRetrOptDepth to RegSfcRetrOptDepth
    SfcRetrModel to RegSfcRetrMixture
    SfcRetrAlgTypeFlag to RegSfcRetrAlgTypeFlag
  • Add new fields:
    OptDepthDWCalcPerBand (not yet populated)
    OptDepthOTACalcPerBand (not yet populated)
    ChisqAbsCalcPerBand (not yet populated)
    RegSfcRetrOptDepthUnc (not yet populated)
    RegBestFitMixtureEqRefl (not yet populated)
  • Reorder regional aerosol parameters within aerosol file
  • Remove obsolete fields ReflParamR0, OptDepthDiffUpBd, OptDepthDiffLoBd, ExtNDVI
  • Rename the dimension NAerModelDim to NAerMixtureDim

Science Config File Changes

  • Rename min_dw_chan_thresh to min_dw_cam_thresh
  • Change values:
    cloud_mask_decision_matrix(1,1): .true. -> .false.
    cloud_mask_decision_matrix(2,1): .true. -> .false.
    cloud_mask_decision_matrix(1,2): .true. -> .false.
    cloud_mask_decision_matrix(2,2): .true. -> .false.
    def_ref_mixt: 51 -> 0
    max_chisq_het_thresh: 4 -> 3
    max_hdrf: 3.0 -> 2.0
    sigma_tau_default: 2. -> 3.
  • Remove parameters: band_mask, min_ddv_chan_thresh,
    min_het_contrast_thresh, max_chisq_abs_ddv_thresh,
    max_chisq_geom_ddv_thresh, max_chisq_spec_ddv_thresh,
    min_r0_ddv_thresh, max_r0_ddv_thresh, toa_r0_ddv,
    k_variance, g_variance, use_t0_t1_for_DDV
  • Add parameters:
    dw_band_mask: .false. .false. .true .true.
    het_band_mask: .true .true. .true .false.
    homog_band_mask: .true .true. .true .false.
    ota_band_mask: .true .true. .true .true.
    bias_pix_flag: .false.
    min_het_stdev_thresh: 0.0
    min_ota_subr_thresh: 32
    min_ota_cam_thresh: 5
    max_chisq_abs_ota_thresh: 3.0
    max_chisq_geom_ota_thresh: 3.0
    max_chisq_spec_ota_thresh: 3.0
    max_chisq_maxdev_ota_thresh: 3.0

Other Ancillary File Changes

  • ACP update: switch to new APOP (Aerosol Physical and Optical Properties) file containing 11 new aerosol component particles.
  • ACP update: switch to new Aerosol Mixture file containing 24 mixtures of new aerosol component particles. This represents a complete revamping of the previous version.
  • Switch to new SMART (Simulated MISR Ancillary Radiative Transfer) dataset containing improved RT (Radiative Transfer) calculations.