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It's not a trivial undertaking... The process we currently employ is based on Franz, et al., (2007)*. In practice it requires running the l2gen code with a particular configuration that inverts the forward process of atmospheric correction. For the NIR (or SWIR) bands used in the aerosol model selec...

Make sure the appkey was entered correctly, as well. The code will fail with the error you saw if the appkey is invalid (mistyped, or expired...We need to update the code trap this error better ).

Sean

First, I'll make the assumption that you replaced {{APP_KEY}} with your app key value

Since you had --verbose set, what (if any) errors did it output?

Sean

If you are looking to change the reflectance for the SWIR bands (or any band for that matter) for processing with l2gen, there is no need to modify the input L1B file. The way to do this with l2gen is to modify the gain parameter. The SWIR gains for MODIS are set to unity as the signal to noise is t...

Note, I did say "it is not supported by all sensors". The MBAC algorithm uses an uncertainty input file to weight the bands used in the fit. Not all sensors have had this file generated, in fact, for most one does not exist. As we implement MBAC for sensor for which it makes sense, we will...

There may be several reasons for a lack of correlation. The empirical algorithm for Kd490 was not developed with data that includes high concentrations of PIC (i.e. coccolithophore blooms). The conditions present during an intense coccolithophore bloom likely violate the assumptions used in the deve...

The earliest implementation of MBAC in l2gen go back to 2016, however, MBAC has not been implemented as a default approach for any sensor to date. However, it will be used for the OCI instrument on the soon-to-be-launched PACE mission. You can try it out with aer_opt=-18, but it is not supported by ...

Julian, Thanks for alerting us to the issue. Adding HISATZEN is a good stop-gap measure for the MLAC data, however it will exclude more than is necessary. Once we have identified the cause for the erroneous data in the SeaWiFS MLAC PAR output (it appears to only affect SeaWiFS MLAC), we determine ho...

The VIIRS I-bands are not supported in l2gen, nor are there any plans to do so.

Sean

The --http_manifest option takes the manifest URL as input, e.g.: ❯ obdaac_download --http_manifest=https://oceandata.sci.gsfc.nasa.gov/cgi/getfile/http_manifest.txt\?h\=ocdist305\&p\=/data1/e030e02b2cfc4c60 -v Retrieving https://oceandata.sci.gsfc.nasa.gov/cgi/getfile/http_manifest.txt?h=ocdist...