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Introduction

Tracking of known problems and subsequent fixes is an important issue for MODIS data users. This Data Issues section of the website will act as a repository of all known MODIS Atmosphere Data Product problems, as well as how to determine the problematic version (and the fixed version) of the HDF data -- therefore data users should check this page for updates regularly. Data Users unfamiliar with how to properly track problems and fixes by determining the version of their downloaded HDF files should refer to the documentation at the bottom of this page.

Data Issues are organized by individual L2 and L3 Product Files. Users may peruse issues for each Product by clicking on the Product links to the left.

How to Track MODIS Data File "Versions" (Important for Tracking Problems and Fixes)

Problems and fixes in MODIS Atmosphere Product HDF files can be tracked in one of two ways:

  1. The Product Generation Executive (PGE) Version Number that can be queried from any HDF file using the command:  ncdump -h *.hdf
  2. The HDF File "Production Date", which is the date the HDF file was actually generated or produced can be found in the HDF filename itself (shown in green color below)
  3. The HDF File "Collection Version", which is a braod generation tag can be found in the HDF filename itself (shown in red color below)

Level 2 Product HDF Filename Format:

Level 3 Product HDF Filename Format:

Note that 1.) all times are UTC time, not local time 2.) the DDD in the date denotes the Day of Year (001-366), and 3.) the prefix (MOD06_L2, MOD08_D3, etc.) is only an example (MYD04_L2, MOD05_L2, MYD05_L2, MYD06_L2, etc. ... or MYD08_D3, MOD08_E3, MYD08_E3, MOD08_M3, MYD08_M3 could be substituted).