Search found 77 matches

by OB General Science - guoqingw
Mon Jul 11, 2022 12:01 pm America/New_York
Forum: Questions/Comments
Question: Missing MODIS L1A files in our subscription since 2 days
Replies: 7

Re: Missing MODIS L1A files in our subscription since 2 days

Hi Jacques,

The problem has been fixed. Please double check.

Guoqing
by OB General Science - guoqingw
Mon Jul 11, 2022 11:15 am America/New_York
Forum: Questions/Comments
Question: Level 3 VIIRS CHL Product
Replies: 2

Re: Level 3 VIIRS CHL Product

Hi Mark, Yes, we provide daily VIIRS level 3 mapped data at 4km resolution and more. There are several ways to download the data. On ocean color website (https://oceancolor.gsfc.nasa.gov/), under the "Data" button, you can click "Direct Data Access", and it will jump to the data ...
by OB General Science - guoqingw
Mon Jul 11, 2022 9:14 am America/New_York
Forum: Questions/Comments
Question: [SeaBASS - MODISA] SST retrieval at night
Replies: 5

Re: [SeaBASS - MODISA] SST retrieval at night

Hi, The SST product you downloaded should be the most recent R2019 version. Here is the document about it: https://oceancolor.gsfc.nasa.gov/reprocessing/r2019/sst/ Details about the algorithms used in SST: https://oceancolor.gsfc.nasa.gov/atbd/sst/ https://oceancolor.gsfc.nasa.gov/atbd/sst4/ https:/...
by OB General Science - guoqingw
Fri Jul 08, 2022 3:15 pm America/New_York
Forum: Questions/Comments
Question: batch extract MODIS spectra without download
Replies: 1

Re: batch extract MODIS spectra without download

Hi Chui, Unfortunately, there is no easy way to do that without downloading the original files. One method that I used may help a little. You can find all the MODIS L1 and L2 files that matches the date and time (+- time differences that you prefer). Then use wget to download all the files, and subt...
by OB General Science - guoqingw
Wed Jul 06, 2022 11:07 am America/New_York
Forum: Questions/Comments
Question: how are 8d/monthly data averaged?
Replies: 1

Re: how are 8d/monthly data averaged?

Hi, It sounds like you may be planning to average the daily mapped files to get 8-day and monthly mapped files. You should use l3 BIN data instead of SMI for that purpose. After binning, you can use the SeaDAS l3mapgen to produce the mapped images. All the standard mean/composite products are calcul...
by OB General Science - guoqingw
Tue Jun 28, 2022 1:10 pm America/New_York
Forum: Questions/Comments
Question: How to derive Lw from Rrs product
Replies: 4

Re: How to derive Lw from Rrs product

The easy way to get Lw is using the l2gen of SeaDAS. Other parameters including brdf can also be obtained from l2gen.
Guoqing
by OB General Science - guoqingw
Mon Jun 27, 2022 1:40 pm America/New_York
Forum: Questions/Comments
Question: How to derive Lw from Rrs product
Replies: 4

Re: How to derive Lw from Rrs product

Hi RG, Do you mind sharing a little detail about why you want to get Lw? If you meant to obtain the nLw (normalized water-leaving radiance, some products use it as standard L2 data), there is a simple equation: nLw = Rrs*F0, and you can find F0 here: https://oceancolor.gsfc.nasa.gov/docs/rsr/rsr_tab...