Level 2 Processing Flags in SeaDAS

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Topic Products and Algorithms / Satellite Data Products & Algorithms / Level 2 Processing Flags in SeaDAS (locked) (2213 hits)

By angira Date 2009-04-17 15:40

Hi:

This is regarding the Level-2 Processing Land Flag that is used to mask the water pixels very close to the coastline to avoid the impact of adjacent land reflectance. Is there a standard "buffer" size considered to mask these pixels ? For a 1 km product how many pixels adjacent to the coast are masked? Is it the same for Chl a, TSS and SST? Also are these flags site specific? My study areas are the Galveston Bay(Texas), Mobile Bay (Alabama) and the Caloosahatchee Estuary (Florida). In order to use 1 km, 500 m and 250 m products, how many pixels near the coast need to be masked to avoid the impact of land reflectance? Can anyone please suggest some literature that discusses this issue?

Thanks!

Angira

By @bryan Date 2009-04-17 18:41

I assume you are asking about MODIS. Straylight is flagged in Level-2, but it is not masked in Level-2. The flagging is 7x5 pixels around any cloud or saturating pixel. This only applies to products derived from water-leaving reflectance (not applied to SST). The masking is defined for 1-km resolution. The flagging should be expanded to 20x35 pixels if processing at 250m.

see:

http://oceancolor.gsfc.nasa.gov/REPROCESSING/Aqua/R1/modisa_repro1_stlight.html
http://www.mcst.ssai.biz/mcstweb/documents/mcst_2006_01_04_meister.ppt
ftp://samoa.gsfc.nasa.gov/pub/franz/papers/meister_et_al_2008_spie.pdf

-- bryan

Topic Products and Algorithms / Satellite Data Products & Algorithms / Level 2 Processing Flags in SeaDAS (locked) (2213 hits)