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General PGE Information

The MODATML2 and MYDATML2 products are produced from the Program Executable (PGE) identified as PGE83.

Tool/Command for PGE Determination

One may identify the maturity and quality of an HDF data product by finding the PGE (program executable) version that was used to produce the file. This information can be obtained directly from the HDF file itself by using the HDF utility ncdump. The (UNIX) command for finding the PGE version that was used to create a particular HDF file is

ncdump -h *.hdf | awk '/PGEVERSIONCLASS/,/END_GROUP/'

One may also find PGE version information in the ascii met (metadata) file associated with a particular HDF file.

PGE83 Algorithm History - Product Impact Changes

PGE83 Version Detail
Product impact changes only
High Impact = High Impact     Moderate Impact = Moderate Impact     Low Impact = Low Impact
(Dates show approximate starting production date)

PGE83 v4.0.1 includes:       ( Terra Forward: ~1.January.2004       Aqua Forward & Reprocess: ~1.January.2004 )

  • L2 Joint Atmosphere (v4.0.1)
      Moderate Impact SDS Ordering Optimization. The order in which SDS's were written (and subsequently appear when using tools such as ncdump, HDFLook, and ENVI) was rearranged so that all 5-km resolution SDS's appear first beginning with their geolocation arrays, followed by all 10-km SDS's beginning with their geolocation and viewing geometry arrays. This is now consistent with other L2 products and is more friendly for users of the ATM L2 product.
      Moderate Impact Precipitable Water Near Infrared Clear local attribute bug fix. Previously, no local attributes were written in the Precipitable Water Near Infrared Clear SDS at night. The decision tree that prevented writing these attributes when the data values were fill (missing) was removed so that this SDS always has local attributes even when all of its data are fill values.
  • Run Time Scripts
      Low Impact Build and Runtime Changes.
      • ECS Core attribute VersionId (the Collection identifier) was changed from 3 to 4 in all Aqua metadata configuration files (MCFs).
      • The SDPTK (Toolkit) configuration was upgraded from 'SDPTK5.2.7v1_64_f77' to 'SDPTK5.2.9v1_64_f90'.

Terra Collection 004 Continues Start of Aqua Collection 004

PGE83 v4.0.0 includes:       ( Terra Forward: ~14.October.2003       Aqua Forward: ~14.October.2003 )

  • L2 Joint Atmosphere (v4.0.0)

      Initial version.

Start of Terra Collection 004 Start of Aqua Collection 003

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