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I have MCD43A3 product and I am using that to get the albedo values(Black sky and White Sky). I have some in-situ snow depth data, corresponding to which I want to get these albedo values.

For most of the in-situ data I'm getting a value of 32767, which is a fill value for the product. For some data I'm getting, a value like 908,889,976 which is multiplied by scale factor of 0.0010 to get the albedo values like .908,.889,.976.

My question is what should I do about the 32767 values which I am getting for most part of my data? Does getting this type of value mean that the image has noise or error? I have little experience with MCD products, any kind of help would be appreciated. Thanks, GBh

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1 Answer 1

up vote 1 down vote accepted

You may want to check this page:

https://lpdaac.usgs.gov/products/modis_products_table/mcd43a3

32767 is actually the fill value, so that's NO DATA (to be removed prior to rescaling). Then rescale the pixel values with 0.0010.

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Thanks for the reply markusN, So that means I have NO DATA for most part of my dataset since most values I am getting are 32767. Is there anything else which can be done for this product apart from getting a new set of images(new days) to get albedo values for those NO DATA region? –  GBh Nov 4 '12 at 22:23
    
Did you get your data from here (which one?): e4ftl01.cr.usgs.gov/MOTA/MCD43A3.005 –  markusN Nov 5 '12 at 22:30
    
I got the data from LPDAAC data retrieval tool for Franklin bay area, Canada 2008 April- July, is there something which cane be done to get the required BSA and WSA values instead of NO DATA? –  user12512 Nov 5 '12 at 23:37
    
I suppose that only time based interpolation (look backward and forward to find valid pixels) is a solution which requires to use a stack of maps. We have developed something similar for MODIS LST: gis.cri.fmach.it/modis-lst –  markusN Nov 6 '12 at 15:09

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