GEDI L2B products : Questions abou noise and nan values

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loriesouza
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GEDI L2B products : Questions abou noise and nan values

by loriesouza » Sat May 25, 2024 8:41 pm America/New_York

Dear colleagues,

While reading about data treatment procedures, I encountered confusion regarding how to proceed with my analysis. I downloaded the rh metrics, specifically the rh bands, from L2B products available on Google Earth Engine. Before downloading, should I clean my data?

I ask because some articles suggest using the parameter "numdetected_modes" for cleaning, or checking elev_lowestmode and the SRTM DEM (digital elevation model srtm). If elev_lowestmode is greater than 100 m, shots will be removed. However, these values are mentioned in the L2A collection. Are they corrected in the L2B collection?

I hope this is clear, as I am still learning English.

Thank you for your attention!

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LP DAAC - jwilson
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Re: GEDI L2B products : Questions abou noise and nan values

by LP DAAC - jwilson » Wed Jun 05, 2024 4:06 pm America/New_York

@loriesouza Thank you for your question. We have forwarded your question to our science team and will write back when we have additional information.

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Re: GEDI L2B products : Questions abou noise and nan values

by LP DAAC - lien » Tue Jun 25, 2024 11:09 am America/New_York

Hi @loriesouza ,
Please see the following response from the science team:

"GEDI V2 collections have gone through extensive accuracy and quality checks with the results included in the metadata. Quality and accuracy layers include degrade_flag, sensitivity, and l2b_quality_flag. Section 6 of the GEDI User Guide describes the quality and interpretation available for each shot (https://lpdaac.usgs.gov/documents/998/GEDI02_UserGuide_V21.pdf).
GEDI Receive Waveform Elevations, Heights, Sensitivity and Quality Inputs is found in Section 5 of the GEDI Algorithm Theoretical Basis Document (https://lpdaac.usgs.gov/documents/581/GEDI_WF_ATBD_v1.0.pdf). SRTM is not recommended to be used for a means to clean the data."

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LPDAAC

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