Search found 75 matches

by OB General Science - guoqingw
Thu Dec 07, 2023 10:06 am America/New_York
Forum: Questions/Comments
Question: getanc socket.timeout
Replies: 6

Re: getanc socket.timeout

@tlin2_cuny.edu @haag
Please email "connection_problems@oceancolor.gsfc.nasa.gov" with the public ip address you are connection from, the time you tried to connect and a short description of the network issue you are experiencing. The NASA OBPG network team will assist you.
by OB General Science - guoqingw
Thu Dec 07, 2023 10:05 am America/New_York
Forum: Questions/Comments
Question: Cannot resolve domain using wget.
Replies: 6

Re: Cannot resolve domain using wget.

Please email "connection_problems@oceancolor.gsfc.nasa.gov" with the public ip address you are connection from, the time you tried to connect and a short description of the network issue you are experiencing. The NASA OBPG network team will assist you.
by OB General Science - guoqingw
Tue Dec 05, 2023 10:44 am America/New_York
Forum: Questions/Comments
Question: Threshold Definition
Replies: 2

Re: Threshold Definition

Hello, The POC algorithm is mainly for open ocean or Case 1 waters, and it relies on the fact that variation in Rrs(λ) at blue wavelengths are primarily driven by phytoplankton pigments and covarying matters. For coastal or optically complex case 2 waters, the empirical relationship used in the algo...
by OB General Science - guoqingw
Thu Nov 30, 2023 12:04 pm America/New_York
Forum: Questions/Comments
Question: Chlorophyll-a algorithm & sediment contamination
Replies: 1

Re: Chlorophyll-a algorithm & sediment contamination

Hi, First of all, here is the theoretic basis for the standard Chlorophyll-a algorithm we use: https://oceancolor.gsfc.nasa.gov/resources/atbd/chlor_a/. Second, yes, for coastal regions, the standard Chlorophyll-a values tend to be higher due to the optical complexity of the water. That said, the op...
by OB General Science - guoqingw
Tue Nov 28, 2023 11:15 am America/New_York
Forum: Questions/Comments
Question: Aqua MODIS gridded ERDDAP chlorophyll
Replies: 2

Re: Aqua MODIS gridded ERDDAP chlorophyll

Hi Anna,

ERDDAP database is maintained by NOAA. You may want to try Earthdata Search (https://search.earthdata.nasa.gov/search).

Let me know if you came across any issues.
Guoqing
by OB General Science - guoqingw
Mon Oct 30, 2023 4:20 pm America/New_York
Forum: Questions/Comments
Question: Accessing and Processing L3 Data in Python with netCDF4
Replies: 2

Re: Accessing and Processing L3 Data in Python with netCDF4

Hello, We are working on sample python scripts for such purposes. These scripts will be available very soon, but here is an example to get you started: L3 data is stored as variables, and you can use xarray to read them: import xarray as xr # use the following file as an example filename = 'AQUA_MOD...
by OB General Science - guoqingw
Fri Oct 27, 2023 10:14 am America/New_York
Forum: Questions/Comments
Question: Data Retrieval Method: Extract or Download?
Replies: 3

Re: Data Retrieval Method: Extract or Download?

Hi, The discrepancies you've observed primarily stem from comparing local min/max values to global ones. When you download without extraction, you receive the Chlorophyll image for the entire globe. On the other hand, using the extract function allows you to isolate the specific region defined by th...
by OB General Science - guoqingw
Thu Oct 26, 2023 10:53 am America/New_York
Forum: Questions/Comments
Question: Chlorophyll product
Replies: 1

Re: Chlorophyll product

Hi Giovanni, You can find all the information regarding the quality flags on this webpage: https://oceancolor.gsfc.nasa.gov/resources/atbd/ocl2flags/ If you are using the L2 products, the flags and masks are included in the file. One easy way to find those info is opening the data file in SeaDAS. Fo...
by OB General Science - guoqingw
Thu Oct 05, 2023 2:15 pm America/New_York
Forum: Questions/Comments
Question: L1A data downloads stop
Replies: 6

Re: L1A data downloads stop

Hi Josep,

It seems the files were located on our server but the downloading was incomplete. Do you mind trying to use the app key and let us know how it works? You can find more details on this page: https://oceancolor.gsfc.nasa.gov/data/download_methods/