Land pixel definition in MODIS SST/ Chlorophyll level 3 data

[samira98]

Dear Support-Team,

I have a question regarding the definition of land pixels in the MODIS Level 3 SST and Chlorophyll dataset (monthly averages, 4km spatial resolution).
When I compare the land pixels of the dataset (pixels spanning multiple datasets, always nan) with a digital elevation model (DEM), I see strong discrepancies. In fact, many of the pixels that are >0m in the DEM, and thus intrinsically land pixels have SST/chlorophyll values. So I was wondering how these ocean/land pixels are distinguished in the MODIS product. Is there a land/sea mask? What is the applied definition for land and sea pixels?

Thank you very much for your help.

[OB General Science - guoqingw]

Hi, not sure what you are trying to do, but here is the tech doc for the land/water mask: https://oceancolor.gsfc.nasa.gov/resources/docs/technical/odps_land_mask.pdf

Hope it helps.