From f00e22a968e4d0740638dcb90fa166d6d7ea05bd Mon Sep 17 00:00:00 2001 From: Matthias Mohr Date: Wed, 8 May 2024 13:21:09 +0200 Subject: [PATCH] Add timeliness example and warning --- README.md | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/README.md b/README.md index fc923db..525f045 100644 --- a/README.md +++ b/README.md @@ -49,6 +49,26 @@ Some extensions may specify more specific rules for this field. This field superceedes the `sar:product_type` field. +#### Timeliness + +Below you can find an example that shows how the timeliness fields could be used. + +The Copernicus programme releases products on three levels of timeliness: + +| Name | Description | `product:timeliness` | `product:timeliness_category` | +| ------------------- | ------------------------------------------------------------ | ----------------------- | ----------------------------- | +| Near Real-Time | Delivered less than 3 hours after data acquisition. | e.g. `PT3H` (3 hours) | `NRT` | +| Short Time-Critical | Delivered within 36 (Sentinel-6) to 48 (Sentinel-3) hours after data acquisition. | e.g. `PT36H` (36 hours) | `STC` | +| Non Time-Critical | Delivered typically within 1 month after data acquisition. | e.g `P1M` (1 month) | `NTC` | + +> \[!WARNING] +> +> Be careful when specifying the durations for `product:timeliness`. It is recommended to closely reflect the semantics of timeliness as specified by the provider. For example, if the timeliness is 36 hours, specify `PT36H` instead of `P1DT12H`, although allowed: +> +> > The standard does not prohibit date and time values in a duration representation from exceeding their "carry over points". Thus, `PT36H` could be used as well as `P1DT12H` for representing the same duration. But keep in mind that `PT36H` is not the same as `P1DT12H` when switching from or to Daylight saving time. +> +> Source: + ## Contributing All contributions are subject to the