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Hi Eligio,Compression ratio will vary depending on the contents of the scene.L2 scenes that have large areas masked out (e.g. for land) willcompress much smaller than those with a more complete andvarying feature set.If I were you, I would set up a processing flow that downloadsscenes serially and d...

Hi Eligio,You can get daily level-2 volumes by adding up the file sizes in bytesfrom pages like this representative Aqua/MODIS page from yesterday.https://oceandata.sci.gsfc.nasa.gov. (/MODIS-Aqua/L2/2020/078/). If you are only interested in coastal regions, you will obviously haveless data to proce...

In addition to heavy suspended sediment load in the Bay of Bengal,the region also suffers from perennially bad air quality.  This negativelyaffects the accuracy of the MODIS atmospheric correction.I am afraid your reviewers are correct.  Ocean color remote sensingis difficult even over cle...

Hi Robert,I've been having some hallway conversations with folks whoknow a lot more about how our sausage is made than I do.The general thinking is that MODIS instrument calibrationis a never-ending process as the aging spacecraft is exposedto the ever changing space environment.  As one ge...

Hi Robert,I was a bit more careful this time, and I do see what you are seeing.The following three images show differences between subsequent8-day 9km composites of adg_443_giop.  Red indicates that adg isgreater in the minuend, while blue shows areas where adg is greaterin the subtrahend. Whit...

Um, strike that image.  I just realized I didn't leave out the "no data" areas.
I'll have another look at this tomorrow, but if you could provide any additional
details in the mean time, that might help make sure I am looking in the
right place.

Norman

Hi Robert,I just computed the difference in the adg_443 values from these two files.A20193292019336.L3m_8D_IOP_adg_443_giop_4km.ncA20193372019344.L3m_8D_IOP_adg_443_giop_4km.ncI got a global field that looks like the attached image where red regions have higheradg in the first 8-day period and blue ...

I don't know what you consider high resolution, but the NASAEarthData folks have a WorldView browser that covers resolutionsdown to roughly 500-meter pixels.https://worldview.earthdata.nasa.gov/The Europeans have a browser for their Sentinel-2 data which have10-meter resolution.https://apps.sent...

Hi Eligio,

As far as I am aware, we do not distribute SMI count files.
Which SMI files are you using?   If you want a proper image
showing the valid number of observations at any location,
then you should be using the L3 bin files as Don and George
suggested.

Regards,
Norman

Hi,

MODIS data have a maximum resolution of 250 meters (at nadir,
for just two bands).  The resolution is limited by the hardware flying
in space.  Representing MODIS data at 30-meter resolution is just
creating data.

Regards,
Norman