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)
  OptDepthHetCalcPerBand
  OptDepthHomogCalcPerBand
  ChisqHomog
  ChisqAbsCalcPerBand (not yet populated)
  ChisqHomogCalcPerBand
  RegEqReflDarkest
  RegEqReflStDev
  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.