Sentinel-3 SL_2_LST data in PDU of Stripe v.s. Frame

Hi folks, as I’m downloading the Sentinel-3 data (SL_2_LST) from the Copernicus Open Access Hub. I get data in two PDUs (product dissemination unit), some in Frame (every ~3mins along track) and some in Stripe (half of an orbit). I’ve searched around but I can’t find a definitive answer whether I can discard the data in the PDU of stripes. Are they just duplicates of the data in the PDU of frames?

Thanks,

The 3-minute PDUs are usually FR (Full-resolution/300m) data. The half orbits are RR data (reduced resollution/1km).

Does this answer your question?

Hi @marpet thanks for your reply! I think this only applies to Sentinel-3 OLCI data products. For Sentinel-3 LST products that are generated from the SLSTR thermal bands, everything is in 1km resolution, isn’t it?

I only found the statement in SLSTR-related documents that SL_2_LST products are gridded in 1km resolution. I can’t find the different resolutions in 3-min PDUs v.s. half-orbit PDUs…

You are right. I’m sorry, I haven’t really noticed that you are talking about SLSTR, even though you said so.
I just looked at the scihub and haven’t LST half-orbits. Can you point to example?
But in general, your question is probably better directed to the scihub.
You can contact them via email: eosupport@copernicus.esa.int

No worries. For example, this one
https://scihub.copernicus.eu/dhus/odata/v1/Products(‘130f110b-ebbb-484e-b57a-0f65b6078865’)

S3A_SL_2_LST____20190901T092107_20190901T110206_20190902T152554_6059_048_364______LN2_O_NT_003

You can see its content length (file size) is close to 2G. In the user guide and ATBD of SL_2_LST, it only mentioned PDUs of 3-min frames. However from my query I got many such half-orbit PDUs…
I’ll message the eosupport. Thanks for sharing the channel.

Okay I just got some answer from the session of “Meet the Land Surface Temperature scientist’ and interact with ESA’s animated globe” at LPS22. For the SL_2_LST data, the PDU of 3-min frames should have all the observations. They are duplicates of the PDUs of half-orbit stripes except the frame-based PDUs mask out oceans while the stripe-based PDUs do not. If I ever find a definitive answer in an official document, I’ll come back and post.

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