Search found 206 matches
- Wed Jun 07, 2023 11:14 am America/New_York
- Forum: Questions/Comments
- Question: Python download script utf-8 UnicodeDecodeError VNP46A1
- Replies: 1
Re: Python download script utf-8 UnicodeDecodeError VNP46A1
The issue is that HDF5 is a binary format, not a text format. There is no text encoding that will work to decode it as text (as you are seeing). The script does also read csv or json files from the web site, to get the directory listings, so it needs to be able to read both text and binary data. Unf...
- Wed Jun 07, 2023 10:50 am America/New_York
- Forum: Questions/Comments
- Question: Read the reflectance of MODIS L1B data
- Replies: 3
Re: Read the reflectance of MODIS L1B data
The MOD03 file has the lat/lon and view geometry at the same resolution as the L1B file. If these fields from an L1B file are to be used an interpolation to account for the different dimensions needs to be performed.
- Mon Jun 05, 2023 9:23 am America/New_York
- Forum: Questions/Comments
- Question: Read the reflectance of MODIS L1B data
- Replies: 3
Re: Read the reflectance of MODIS L1B data
The MOD021KM files contain radiances and reflectances, What's stored in the files are HDF Scientific Data Sets (SDSs), each of which has a "long_name" attribute that ends with "Scaled Integers". The values store in those SDSs are scaled integers, (abbreviated SI). You need to use...
- Wed May 31, 2023 6:19 am America/New_York
- Forum: Questions/Comments
- Question: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
- Replies: 5
Re: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
We further looked into the granules to check the Aerosol Optical Depth (AOD) pattern you reported and below is the summery: The Missing Aerosol Optical Data (AOD) is not the systematic issue. They are relevant to the pixel selections. For the following conditions, the AOD values will be fill valu...
- Tue May 30, 2023 7:57 am America/New_York
- Forum: Questions/Comments
- Question: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
- Replies: 5
Re: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
Also, the Dark Target AOD cannot be retrieved over brighter surfaces. So, you may be getting confused by an apparent pattern that forms over the equatorial and tropical areas, where most of the areas are brighter because of clouds and deserts, and so there is not much retrieval of DT AOD, creating o...
- Fri May 26, 2023 11:58 am America/New_York
- Forum: Questions/Comments
- Question: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
- Replies: 5
Re: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
Dear Laxmi: Please note the following: Have you tried to cross-reference the missing areas with the MODIS cloud mask (MxD35_L2) to see if those areas have persistent cloud. You can also reference a RGB reflectance image for this. With regard to this question: coverage of the MODIS swath keeps on cha...
- Mon May 22, 2023 11:50 am America/New_York
- Forum: Questions/Comments
- Question: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
- Replies: 5
Re: Missing Aerosol Optical Depth (AOD) Data in MYD04_L2
Dear Laxmi:
Can you provide an example from files that exhibit such behavior (couple of file names should be sufficient)?
Can you provide an example from files that exhibit such behavior (couple of file names should be sufficient)?
- Thu May 18, 2023 8:55 am America/New_York
- Forum: Questions/Comments
- Question: VIIRS VNP46A2 timestamp acquisition time
- Replies: 1
Re: VIIRS VNP46A2 timestamp acquisition time
This is because VNP46A2 is a daily products containing observation for the 24h period. You can find UTC-Time parameter in VNP46A1 product that lists UTC view time (the time of data acquisition). For more information consult product users guide at: https://ladsweb.modaps.eosdis.nasa.gov/api/v2/conten...
- Tue May 16, 2023 7:15 am America/New_York
- Forum: Questions/Comments
- Question: Request the bi-values needed to calculate LST using the Generalized Split Window (GSW) algorithm with the MYD021KM produ
- Replies: 3
Re: Request the bi-values needed to calculate LST using the Generalized Split Window (GSW) algorithm with the MYD021KM p
Here at LAADS DAAC we don't have contact information for land products' science team members. The product PI for LST is Zhengming Wan at ERI, University of California, Santa Barbara so you can check there. You can contact NASA'S Land Processes Distributed Active Archive Center (LP DAAC), the primary...
- Mon May 15, 2023 10:12 am America/New_York
- Forum: Questions/Comments
- Question: No MYD35_L2 data for April 2023
- Replies: 1