Search found 1361 matches

by OB.DAAC - SeanBailey
Thu Oct 20, 2022 9:13 am America/New_York
Forum: Questions/Comments
Question: modis_L1B output depends on MODIS granule date ?
Replies: 3

Re: modis_L1B output depends on MODIS granule date ?

Jacques, The A2020168174500.L1A_LAC scene is a nighttime scene: https://oceancolor.gsfc.nasa.gov/cgi/browse.pl?file=AQUA_MODIS.20200616T174501.L2.SST.nc_SST_BRS By default, the modis_L1B script disables the HKM and QKM output for nighttime granules as the 250 and 500m bands are only reflective solar...
by OB.DAAC - SeanBailey
Wed Oct 19, 2022 12:13 pm America/New_York
Forum: Questions/Comments
Question: Where can i find the algorithm theoretical basis document of SeaDAS?
Replies: 3

Re: Where can i find the algorithm theoretical basis document of SeaDAS?

In the Rrs ATBD page Alicia pointed out, there is a link to a NASA Technical Memorandum document that goes into great detail on the atmospheric correction process - including the derivation of the glint and foam radiances you mentioned. Since it might easily be missed, here is the link: https://ocea...
by OB.DAAC - SeanBailey
Wed Oct 19, 2022 11:56 am America/New_York
Forum: Questions/Comments
Question: SST4 product no longer distributed?
Replies: 2

Re: SST4 product no longer distributed?

The SST4 product is available, but if you used the L1/2 browser and only had the 'day' checkbox selected, SST4 would not be found. SST4 is only available at night. Try your query again, but select 'night' on the first page (you'll probably aslo have to click the Reconfigure Page button). Regards, Sean
by OB.DAAC - SeanBailey
Tue Oct 18, 2022 2:21 pm America/New_York
Forum: Questions/Comments
Question: I want to convert kd490 unit
Replies: 5

Re: I want to convert kd490 unit

Sure, Kd490 can be used as a proxy for turbidity, with the caveats I mentioned earlier. As Jim points out that euphotic depth can also be used as a proxy for turbidity - euphotic depth is the 1% light level. In my earlier post I suggested you may consider deriving the first optical depth - the 37% l...
by OB.DAAC - SeanBailey
Tue Oct 18, 2022 10:51 am America/New_York
Forum: Questions/Comments
Question: R2022 processing
Replies: 3

Re: R2022 processing

Mati, Not a silly question at all. The second element of the returned CSV is the filename, while the fifth element is the URL to download the file. So, you could do something as simple as this: $ curl --silent -d "page_size=2000&sort_key=short_name&sort_key=start_date&short_name=Sea...
by OB.DAAC - SeanBailey
Mon Oct 17, 2022 3:04 pm America/New_York
Forum: Questions/Comments
Question: MODIS Terra geolocation files
Replies: 4

Re: MODIS Terra geolocation files

When we reprocess the MODIS Terra ocean color data as part of the R2022 reprocessing effort, we will begin archiving and distributing the geolocation files as we did when we reprocessed MODIS Aqua. So, it's coming...soon.

Sean
by OB.DAAC - SeanBailey
Mon Oct 17, 2022 10:59 am America/New_York
Forum: Questions/Comments
Question: R2022 processing
Replies: 3

Re: R2022 processing

Mati, I'm assuming you're not finding the data on the L1/2 browser...the reason is complicated, but boils down to the fact that the L1 filenames were forced to have a start time that matched the start time for the GAC file of the orbit containing the LAC data. With our new naming convention, we're e...
by OB.DAAC - SeanBailey
Wed Oct 12, 2022 12:57 pm America/New_York
Forum: Questions/Comments
Question: I want to convert kd490 unit
Replies: 5

Re: I want to convert kd490 unit

Well, Kd490 is not a measure of turbidity, it's a measure of diffuse attenuation. Turbidity is effectively a measure of scattering. While scattering is part of attenuation, it is not everything, as attenuation also includes absorption. So there is a relationship between turbidity and Kd490, but it i...
by OB.DAAC - SeanBailey
Tue Oct 11, 2022 1:34 pm America/New_York
Forum: Questions/Comments
Question: An error when processing viirs Ibands with Seadas
Replies: 8

Re: VIIRS-JPSS1 l2gen failure after R2022.14 tag instalation

Josep, Seems we missed a required modification to the LutUtils.py code. For the previous reprocessing, JPSS1_VIIRS did not require an xcal file, so LutUtils.py didn't look for them to pull down. Until we can get the change into a tag, you can make the following change to $OCSSW_BIN/seadasutils/LutUt...
by OB.DAAC - SeanBailey
Fri Oct 07, 2022 1:19 pm America/New_York
Forum: Questions/Comments
Question: An error when processing viirs Ibands with Seadas
Replies: 8

Re: An error when processing viirs Ibands with Seadas

NOAA provides a surface reflectance product that includes the I-bands: https://www.ospo.noaa.gov/Products/land/sr/