ESA Copernicus data access - Long Term Archive and its drawbacks

put some products in your cart, you will then be given a python script which assists you to download these data.
I suppose you can easily use parts of the script to automate the download process. I am not sure about searching to be honest.

Thanks a lot. I will definitely try it and let you know the results.

It still requires a bit amount of “handmade” process and clicks, but that’s better than nothing :wink:

for bulk downloading, I mostly use ASF because of the reasons you mentioned. But I sometimes have the feeling that they are missing some of the products.

There is an API for searching as well: https://www.asf.alaska.edu/get-data/api/search-download/

You probably should (worry).

I noticed (in sci-hub) that I occasionally see GRD data, but not their corresponding SLC images. So from time to time, I made a list of these detected images and send them to eosupport. Within few days, I receive a confirmation that these SLC data are in fact missing and thus are added to the database.

I don’t know how ASF handles its database but I’m not sure these old SLC images are tracked by ASF

I’ve a branch of sentinelsat with some additional code for retrieving products from the long term archive
https://github.com/gbaier/sentinelsat/tree/lta_async. One word of warning, the code is still experimental. In essence the download_all function puts LTA-products on a queue and periodically tries to trigger their retrieval. This works around the user quota. Already online products are downloaded while waiting for the LTA-products.

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This means a 1 image per hour image retrieval if I’m right?

Thanks a lot for your developments

My latest info is that users can request a product from the long term archive every 30 minutes. But this is a quota set by the Copernicus open access hub.

For the sake of completeness, ESA also provides a download script that deals with products in the long term archive https://scihub.copernicus.eu/userguide/BatchScripting#dhusget_script.

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thanks for the link.

Quentin

Did anyone find any stable solution? I have a list of product IDs now how I can download them using a script?

I think the best you can do is to use alternative mirrors such as PEPS or ASF.

I contacted the eosupport for the Sentinel platform but their response doesn’t fit with my needs :

[…] you try an bypass the quota restrictions by using multiple user accounts to access large volumes of data products from the LTA. Please note that the maximum number of products that a single user can request on SciHub is 1 every 30 minutes. An additional quota limit is applied to users of the APIHub of maximum 20 products every 12 hours. These restrictions are dictated by ESA and unless they change their policy then users will have to follow these guidelines. […]

So I guess you will not find what you need using the “official” sci-hub.

Note : in their response, they pointed out the importance this type of requests in order to understand people needs. So feel free to contact them to let them know the issue.

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Hi, your branch looks looks really useful to workaround this issue. I use sentinelsat (not a dev) and am wondering if you plan to merge this back in via pull request if its working well for you? Cheers

Upstreaming would be great and is also my goal. I still have to debug some issues though. Another problem is, that it currently relies on some Python3 only features.

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So this will continue running and giving the error # 429 Too Many Requests until it has downloaded each imagery (one per half hours mark)?

The LTA code is now part of sentinelsat https://github.com/sentinelsat/sentinelsat. But there hasn’t been a new release yet, so you have to install from the master branch.

Documentation on how to use it is below.

SNAP8.0 provides access to ASF as well so for older products that should provide a workaround. It would be possible to improve the Copernicus Hub access but my impression has been that most users use standalone tools for access in any case(?).

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@mengdahl Excellent news ! Will it be possible to use GPT to download images with SNAP8 ?

Hi

Seems that the LTA policy affect also several tools, among them DIAS platforms. For me, as am using Sentinel 2 data for now, a workaround solution is the use of EarthExplorer of USGS which has all S2 images from 2015 onwards (at least for my region where i work now).

Is quite annoying that official, public paid tools are not working as expected …

Hope that this will change soon.

D.

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I am also working with S1 time-series and try to somehow automate making “full use” of my user Quota by writing python scripts.
The links provided in this post seem to be very useful and I will check it out soon.
However I am just starting with using python so I face some issues here and there.

I would like to discuss these in this forum, that I really like so far for getting really quick and on point replies and finding a lot of resources browsing through old posts.
Is it therefore possible to open a sub forum e.g. on data retrieval for that?
It seems that this Info is relatively spread, but it would be thematically fitting here, because obviously you need data for working with SNAP or the modules from the Sentinel-toolboxes and manual downloading is not an option for many up to date scientfic tasks like time series extraction or environmental parameter retrieval. And it is like dpoursanidis and others pointed out that ESA should be interested in enabling users for access to all the sentinel data anytime.

Cheers and thanks for the good work everybody,

K.

You can open a new topic in the #development section, although some already exist, e.g. Downloading data for snap using sentinelsat API - LTA error

In this forum we surely have little impact on the data dissemination strategies of ESA, but of course its a good platform for exchange how others deal with the drawbacks of the LTA.

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In addition to what @ABraun says, ESA Copernicus support is quite easy to join (eosupport@copernicus.esa.int). Don’t hesitate to give a feedback, it’s part of their job.

Cheers,

Quentin

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