Negative values in SO2 column amount

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Negative values in SO2 column amount

by EarthdataForumContributor » Fri Jun 26, 2020 7:13 pm America/New_York

I am using the "SO2 Column Amount (Planetary Boundary Layer) OMSO2e v003 (OMSO2e v003)" product for my research work, but I am finding a problem in the range of this product. It has ranged from negative values, which is confusing for me. How can the value of sulphur dioxide at any point be negative?

GES DISC - jimacker
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Re: Negative values in SO2 column amount

by GES DISC - jimacker » Fri Jun 26, 2020 7:14 pm America/New_York

The negative SO2 values are artifacts of the retrieval process. They are usually associated with retrievals over highly reflective surfaces. The OMSO2.003 ReadMe has more detail than is contained in the OMSO2e ReadMe.
https://aura.gesdisc.eosdis.nasa.gov/da ... .OMSO2.pdf

The OMSO2e (Level 3) is aggregated from the Level 2 product so the negative values remain. While negative values are not physically real, the measurements are still valid and should not be discarded.

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