PURPOSE
=======
At LAADS (Level 1 and Atmosphere Archive and Distribution System) we
have received a number of requests from data users for a simple
geographic text file that can be used to delineate the boundaries
of MODIS Level 2 swath products. In response, we have developed the
GeoMeta product file that contains granule corner-point latitudes and
longitudes along with north/south/east/west bounding coordinates.
The data for these parameters are taken directly from the Collection
5 MODIS Geolocation Products, MOD03/MYD03.
A GeoMeta product file covers a complete data day (00:00 - 24:00)
spanning exactly 288 MODIS 5-minute granules. Other parameters not
mentioned above include the Collection, OrbitNumber, and
DayNightFlag. Note that the DayNightFlag refers to the MODIS
instrument setting, whether it is in day mode (D, transmits all
bands), night mode (N, excludes solar bands) or both modes (B,
switches Day to Night or Night to Day).
DATA FORMAT
===========
The first three lines in the GeoMeta product begin with the '#' sign
and contains the following information: (a) GeoMeta title line and
data date; (b) updates to GeoMeta files are revised approximately
every hour with current granule counts for the dataday and the
latest ingest date/time; (c) column headers separated by commas.
Immediately following are comma-separated data fields for each of
the 288 granules.
Part of a sample file with filename of MOD03_2000-10-01 is shown as below:
# MODIS Terra GEOGRAPHIC METADATA TEXT FILE day 2007-10-01
# NFiles = 288, max geo IngestTime = Oct 3 2007 7:55:54:000PM
#
GranuleID,StartDateTime,ArchiveSet,OrbitNumber,DayNightFlag,EastBoundingCoord,NorthBoundingC
oord,SouthBoundingCoord,WestBoundingCoord,GRingLongitude1,GRingLongitude2,GRingLongitude3,GR
ingLongitude4,GRingLatitude1,GRingLatitude2,GRingLatitude3,GRingLatitude4
MOD03.A2007274.0000.005.2007274123016.hdf,2007-10-01
00:00,5,41410,N,10.8895623790675,-40.02119
43293331,-61.985657072234,-30.8508020500087,10.8909073745158,-30.6927900395239,-30.853554112
6505,-1.873
33932142459,-56.0525348895312,-61.9571366911384,-43.7354567284193,-39.8676899816057
STATUS OF THE GeoMeta FILE
==========================
The GeoMeta file is a non-official MODIS product.
DATA ACCESSIBILITY
==================
The GeoMeta files are available at:
https://nrt3.modaps.eosdis.nasa.gov/archive/geoMeta
The daily GeoMeta files are sorted by Collection number,
mission name, and data years, so users need go to
https://nrt3.modaps.eosdis.nasa.gov/geoMeta/{6, 61}/{TERRA,AQUA}/$Year
to pull the daily GeoMeta files they need, where {6, 61} in the directory path
corresponds to MODIS Collection 6 or Collection 6.1, and
{TERRA, AQUA} represents the Terra or Aqua Satellite.