Search found 1166 matches

by OB.DAAC - SeanBailey
Mon Jun 21, 2021 9:07 am America/New_York
Forum: All Questions/Comments
Question: Rayleigh optical thickness for airborne sensors
Replies: 2

Re: Rayleigh optical thickness for airborne sensors

The estimates of top-of-atmosphere Rayleigh radiance in the processing of satellite-based ocean color sensors requires radiative transfer simulations that account for the spectral bandpass of the sensor and an estimate of the surface component as modulated by a roughened ocean (using windspeed to de...
by OB.DAAC - SeanBailey
Thu Jun 17, 2021 12:09 pm America/New_York
Forum: All Questions/Comments
Question: turbidity flag
Replies: 1

Re: turbidity flag

That's pretty much it. The closest band to 670nm is used. If the Rrs in that band is > 0.012, the flag is set.

Sean
by OB.DAAC - SeanBailey
Wed Jun 16, 2021 4:46 pm America/New_York
Forum: All Questions/Comments
Question: L2 Flags being produced instead of selected bands
Replies: 6

Re: L2 Flags being produced instead of selected bands

Nothing jumps out as a problem in the ncdump, so maybe the reader is just getting confused by the 3D products. Specifying <product>_nnn will work as the "_nnn" (or _vvv) gets expanded to the wavelength list. NOT specifying one (i.e. just 'Lt' or 'Rrs') generates a 3D dataset. You could try...
by OB.DAAC - SeanBailey
Wed Jun 16, 2021 12:46 pm America/New_York
Forum: All Questions/Comments
Question: reprojection information not recognized
Replies: 1

Re: reprojection information not recognized

The HDF5 export does include the reprojection information, but may not be stored in a way that is supported by ENVI or E-COGNITION. You might try one of the other output formats, but you may just have to provide the information manually to these external tools.

Sean
by OB.DAAC - SeanBailey
Wed Jun 16, 2021 10:47 am America/New_York
Forum: All Questions/Comments
Question: OLCI Data Download
Replies: 4

Re: OLCI Data Download

This is a case of a 'near miss'. The resolution of the bins used in the spatial matching is about 72km.
https://oceancolor.gsfc.nasa.gov/browse ... uadsphere/

The edge of this scene gets tantalizingly close to the Bay:
Screen Shot 2021-06-16 at 10.36.40 AM.png
Screen Shot 2021-06-16 at 10.36.40 AM.png (412.09 KiB) Not viewed yet
Sean
by OB.DAAC - SeanBailey
Wed Jun 16, 2021 9:14 am America/New_York
Forum: All Questions/Comments
Question: L2 Flags being produced instead of selected bands
Replies: 6

Re: L2 Flags being produced instead of selected bands

Providing l2gen a parameter list that includes spectral products without the wavelength specifier (e.g. Lt vs Lt_412 or Lt_nnn) indicates to the program that you want a three dimensional output array for the product (pixel, line, wavelength). The currently distributed version of l2bin does not recog...
by OB.DAAC - SeanBailey
Mon Jun 14, 2021 8:13 am America/New_York
Forum: All Questions/Comments
Question: seadas l2gen
Replies: 1

Re: seadas l2gen

That's because those products are not supported. For taua_869 use aot_869, the alias taua isn't happy. gsm01 is just gsm and clark was yanked out of service years ago.

Sean
by OB.DAAC - SeanBailey
Thu Jun 10, 2021 10:42 am America/New_York
Forum: All Questions/Comments
Question: MODIS L1 to L2
Replies: 3

Re: MODIS L1 to L2

Kinda need to know where you're looking...Is your region of interest still the Chesapeake Bay? If so, I just ran a query using the L1/2 browser and for 2003 there were 512 granules that matched. 2019 there were 509 granules that matched. That doesn't jive with your report of 80 missing days. In fact...
by OB.DAAC - SeanBailey
Wed Jun 09, 2021 4:08 pm America/New_York
Forum: All Questions/Comments
Question: MODIS L1 to L2
Replies: 3

Re: MODIS L1 to L2

Please provide the dates and region of interest. In general, there are days, or portions of days for which the sensor was not collecting data for one reason or another. If you can provide more information about the specifics of the data you believe to be missing, we may be able to provide an explana...
by OB.DAAC - SeanBailey
Wed Jun 09, 2021 4:04 pm America/New_York
Forum: All Questions/Comments
Question: OLCI Data Download
Replies: 4

Re: OLCI Data Download

Without an example, I can't say. Do you have a specific file or at least a time period for a search that resulted in an erroneous spatial retrieval?

Sean