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Hi XuanYang, Thank you. Is there a way to access the removed 590nm to 610nm bands in the L2 files? They are critical to a coastal ocean algorithm we are testing. We reached out to OB.DAAC and it was mentioned that these bands are still embedded in the L2_AOP product and can be accessed when download...

Hi Tommy, Interesting, my ncdump must be having issues... In the wavelengths you gave in your reply, I noticed that the data is missing bands 590nm - 610nm, which have been removed in the V3 processing cited on the OB.DAAC website. However, when I open a V3 .nc file in SeaDAS (directly downloaded fr...

Hi All, I am working with L2_AOP OB.DAAC PACE OCI product, which according to SeaDAS has a pixel spacing of 1.2km x 1.1km. However, I understand that each of these pixels is actually a combination of 4 scan line swaths that are about 1.2km x 250m each. They are added together to improve the SNR, and...

Hi All, I used to be able to access the PACE wavelengths that corresponded to wavelength_3d for the L2_AOP PACE V3 product with either this code: dataset_band_pars = xr.open_dataset(paths[0], group="sensor_band_parameters") wavelength_3d = dataset_band_pars["wavelength3d"] or ncd...

Hi Tommy, Thanks for the help. I see on the Earthdata portal that the Temporal Extent is '2024-03-05 ongoing,' but when I query results in the Chesapeake Bay through the portal, there are no resulting granules: ED_Browser.PNG I also get no granules when running earthaccess on Python: EA_code.PNG Not...

Hello, I am trying to understand the changes that PACE OCI Level-2 AOP V3.0 has undergone. From OB.DAAC (https://oceancolor.gsfc.nasa.gov/data/reprocessing/V3.0/pace/), I have gathered that these are the key changes: 1.application of system vicarious calibration gains 2.correction for residual sensi...

Hello, I am trying to understand the processing undergone for the Level-2 PACE-OCI Spectral remote sensing reflectances product (OC_AOP) (Version 2, though V3 was recently released). As I understand it, this product provides Rrs in sr-1 units. What is the atmospheric correction algorithm used to gen...

Thanks all for the support. So the process to go from L1A to L2 includes two steps, each with ifile, ofile, and geofile: 1. calibrate_viirs create L1B : ifile=[VIIRSN.L1A.nc] l1bfile_mod = [VIIRSN.L1B.nc] (ofile and geofile are not valid params https://seadas.gsfc.nasa.gov/help-8.1.0/processors/Proc...

Hi Tommy, Thanks. So if I am understanding correctly, I can download the GEO file and use that as a parameter for l2gen? Do I still need to generate L1B with calibrate_viirs then? Can I just generate an l2 directly from l1a with a command like this: "l2gen ifile={l1a_file} ofile={output_name} g...

Hello, I know I have asked many l2gen questions in the past week, so thank you in advance for your patience. I am currently trying to run l2gen on L1A VIIRS-SNPP data (scene: SNPP_VIIRS.20230712T180000.L1A.nc ). I am starting by running calibrate_viirs on the L1A scene to generate L1B. To do this, I...