Limited SWOT Nadir Data?

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Limited SWOT Nadir Data?

by reythia » Fri Jan 05, 2024 2:02 pm America/New_York


I'm trying to figure out how to use the data downloader to only download ONE of the three nadir SWOT iGDR types (dataname: SWOT_L2_NALT_IGDR_1.0). I can and have successfully downloaded all of the types, but that's incredibly wasteful, since it includes:
1). Reduced datasets (filenames beginning with SWOT_IPR)
2). Standard datasets (SWOT_IPN)
3). Expertise datasets (SWOT_IPS)
No one will ever want to download all three, since they're subsets of each other. But I can't find a way to only download one! Please help? I'm sure you don't want people like me hammering your system if we can avoid it, too!

Also, FYI, your example "simple" download does not work, presumably because the dates are wrong for the data series:
podaac-data-downloader -c SWOT_L2_NALT_IGDR_1.0 -d ./data --start-date 2022-12-16T00:00:00Z --end-date 2022-12-23T00:00:00Z -e ""

Jenni Bonin


PODAAC - celiaoued
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Re: Limited SWOT Nadir Data?

by PODAAC - celiaoued » Mon Jan 08, 2024 6:38 pm America/New_York

Thanks for bringing up the example command and trying it out! Can you let me know where you found it so that I can confirm the source that needs to be corrected?

To make the command work, change the dates to between 2023-06-21 and 2023-11-16 for version 1.0, or between 2023-11-16 and present for version 2.0, such as:
podaac-data-downloader -c SWOT_L2_NALT_IGDR_1.0 -d ./data --start-date 2023-11-13T00:00:00Z --end-date 2023-11-16T00:00:00Z
podaac-data-downloader -c SWOT_L2_NALT_IGDR_2.0 -d ./data --start-date 2023-11-16T00:00:00Z --end-date 2023-11-18T00:00:00Z

As a solution to the multiple file types issue you describe, we are working on making sub-collections available and fully integrated with tools and services in the near future. Sub-collections (SWOT_L2_NALT_IGDR_SSHA_2.0, SWOT_L2_NALT_IGDR_GDR_2.0, etc.) are the same data as their parent collection (SWOT_L2_NALT_IGDR_2.0), but partitioned out by file type. These sub-collections currently publicly available for nadir altimetry, though they might not yet cover the entire time period of the parent (I will check on this).

An alternative solution is to selectively download from the parent collection, by using the granule name option and filename pattern with wildcard as below (currently the 'gr' option does not combine with time range selection, so the command ends up downloading all available granules with the specified name pattern, but we are working to fix this as well):

podaac-data-downloader -c SWOT_L2_NALT_IGDR_2.0 -d ./data --start-date 2023-11-16T00:00:00Z --end-date 2023-11-18T00:00:00Z -gr SWOT_IPR_*

Please feel free to reach out with further questions,

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