Nomenclature MODIS files

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jcfischer
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Nomenclature MODIS files

by jcfischer » Tue Jan 30, 2018 5:37 am America/New_York

Hi, I have a question regarding the nomenclature of MODIS files: let´s for example look at the files representing the first of January 2004: A2004001103000.specific-ending.
What does the "A" stand for? "2004" represents the year 2004 and the following "001" represents the first day in the year. Can also the rest (103000) be decoded?
Then there are specific endings of the file names:  L2_LAC_OC.x     -->  level 2 file of ocean color products
                                                                         L2_LAC_SST.x    -->  level 2 file of sea surface temperature products
                                                                         L1A_LAC.x.hdf    -->  level 1A file
What does LAC stand for?
Thanks in advance!

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OB ODPS - towens
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Nomenclature MODIS files

by OB ODPS - towens » Tue Jan 30, 2018 6:56 am America/New_York

"A" indicates Aqua, the platform carrying the MODIS sensor. There are also "T" files from MODIS on Terra.
103000 = 10:30AM Greenwich Mean Time (GMT) , the start time of the granule. You may also see this written as 1030Z (Zulu Time) which is a military designation for the time at the 0° meridian.
"LAC" is "Local Area Coverage".  You May also see "GAC", which is "Global Area Coverage"
?Tommy

jcfischer
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Nomenclature MODIS files

by jcfischer » Tue Jan 30, 2018 7:47 am America/New_York

So it is A-year-day-hour-minute-second.level_Lac_
Thank you very much for the clarification!

OB WebDev - norman
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Nomenclature MODIS files

by OB WebDev - norman » Tue Jan 30, 2018 8:58 am America/New_York


fredoceansips
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Nomenclature MODIS files

by fredoceansips » Tue Jan 30, 2018 10:20 am America/New_York

The complete L2 file naming convention is described in the Ocean Level-2 Data Format Specification:
https://oceancolor.gsfc.nasa.gov/docs/format/l2nc/

Fred

jcfischer
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Nomenclature MODIS files

by jcfischer » Tue Feb 13, 2018 12:30 am America/New_York

Thanks! Don´t know how I missed that.

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