Granules meeting search criteria contain no data

I recently ran into a problem with downloading data and I am wondering if you could help me understand what is going wrong.

From icepyx, I used:

print(region.avail_granules(ids=True))

to gather a list of granules that matched my search criteria, and then I did:

region.download_granules(data_home)

to download the data.

This is the error I receive:

I am confused because it seems that it is telling me there is a granule available, but then it is saying that there is no data?

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Welcome @nina.aragon to the Pangeo Discourse Forum. I don’t have an answer for you question but I bet @JessicaS11does!

Welcome @nina.aragon, and thanks for posting your question!

You’re right to be confused by these contradictory messages! They’re the result of using granule (file) metadata to perform an initial, fast search for data prior to order/download of that data. The initial query step (region.avail_granules()) uses summary metadata to identify granules that likely have data where you’re interested, so it often returns a few granules that might have a few border pixels within your area of interest. However, when the subsetter actually runs (as part of region.download_granules()), it’s finding that there are no data points within your region of interest. Figure 1 on this page has a pictorial representation of this phenomena that can be helpful to understand what’s going on.

In short, what the error is telling you is that there is no ICESat-2 data available for the region (and time period) you specified. NSIDC is also working to minimize this issue (by improving the granule metadata) and provide clearer error reporting. If you have found data for the constraints you are using through another source (e.g. Earthdata or OpenAltimetry), then that points to a potential issue in icepyx that we should look into.

I’d suggest expanding either your temporal or spatial search parameters to see if you can find some data for your area. Please let us know if you continue to have this issue.