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Although extraction of SeaWiFS files works perfectly and really eases downloading of huge files there are some problems with MODIS files. Can you please comment upon the situation I'll describe below?
I ordered SeaWiFS MLAC and MODIS LAC data and marked in the "Scene Order Form" that I want my SeaWiFS data to be extracted. It is written there that "This extraction currently only applies to SeaWiFS files." so I was ready to download extracted SeaWiFS and full MODIS files. However, both the SeaWiFS and MODIS files that were placed to FTP had the following extension: ".x.hdf.bz2" Which basicaly means that they were extracted. These files indeed were extracted and had reduced size so first time I was glad, but...
But then I discovered that one of the MODIS ".L2_LAC.x.hdf.bz2" files was almost empty. I wrote "almost" because it contained only HDF header without L2 products. I again tried to download extracted MODIS file and I'm shure that I checked the box "L2". The result with the same file was absolutely the same. It was almost empty while other files in the order were extracted and contained good data.
The second dissapointment with this 'extraction on demand' for MODIS files was when I received extracted file but its geolocation wasn't right. I saw that pixels had wrong values of lat/lon when I placed coastline over the image (I made it in SeaDAS).
So, what is up with MODIS extraction?
I also have one separate question. As far as your search and ordering engine is very powerfull and convenient I would very happy to use it for search for SeaWiFS data starting from 1997. Is this data avaliable already? (Maybe I missed something...) Or are you planning to enlarge you archive and create SeaWiFS MLAC archive from 1997?
Thank u for your earlier answers!!
The Level 2 extract option now applies to both SeaWiFS and MODIS. We will update the information on the browser to reflect this. Sorry about the confusion there.
I was unable to replicate your problem of 'almost' empty MODIS extracts. Each test I ran correctly extracted the data. If you send me the specifics on the file you had trouble with I may be able to comment more.
The problem with geolocation of the MODIS extracts appears to be an issue with the way SeaDAS is reading in the file. The files themselves contain the correct geolocation information. This SeaDAS problem is being looked into now.
As for MLAC for the entire mission, this is already available.
I have a fix now for the problem in SeaDAS that was giving the bad lat/lons.
Are you using your own installation of IDL or the embedded IDL? If you are
using the embedded IDL,then I will have to go back and rebuild the tar file for
you. If you are using your own installation of IDL, then I can simply e-mail you
the routine and you can slap the file in the $SEADAS/idl_lib directory, and
you should be good to go. Just give me an e-mail address.
Thanks for reply.
My e-mail is firstname.lastname@example.org
Sean, can you, please, specify the link where I can find MLAC for the entire SeaWiFS mission? I used to start searchig for images from http://oceancolor.gsfc.nasa.gov/cgi/browse.pl?sen=am
but the calendar on that page starts only from 2002 and I need images taken in 1998, 1999 etc.
:oops: Sorry, just forgot to say that IDL on my computer is not embedded into SeaDAS.