# LICENCE

## Legal Notice and Terms of Use

This repository contains scientific software and associated research data products.
Different licensing terms apply to software components and data products, as set out below.

In applying these licensing terms, ECMWF does not waive the privileges and immunities granted to it by virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.

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## 1. Software Components

All source code, scripts, workflow definitions, configuration files, and related technical materials contained in this repository (the “Software”) are made available under the:

**Apache License, Version 2.0**, as published by the Apache Software Foundation (the “Apache 2.0 License”).  

A copy of the Apache 2.0 License is available at: 

https://www.apache.org/licenses/LICENSE-2.0

The Software is distributed on an “AS IS” basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including without limitation any warranties of merchantability, fitness for a particular purpose, or non-infringement. The Apache 2.0 License sets out the permissions, conditions, and limitations governing use, reproduction, modification, and distribution of the Software.

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## 2. Data Products

All datasets, derived products, processed outputs, associated metadata, and documentation describing or accompanying such data (the “Data Products”) are made available under the:

**Creative Commons Attribution 4.0 International License (CC BY 4.0)**, published by Creative Commons.

A copy of the CC BY 4.0 License is available at:

https://creativecommons.org/licenses/by/4.0/

Under CC BY 4.0, users may copy, distribute, transmit, adapt, and build upon the Data Products for any purpose, including commercial purposes, provided that appropriate credit is given, a link to the license is provided, and any modifications are clearly indicated.

The data products also include ECMWF OpenIFS data products, historic IFS data products, static IFS input data (ifsdata), Copernicus Climate Change Service (C3S) ERA5 data products and Copernicus Atmosphere Monitoring Service (CAMS) data products.

Unless otherwise stated, the Data Products are provided without warranty of any kind, either express or implied, including, but not limited to, warranties of accuracy, completeness, fitness for a particular purpose, or suitability for specific applications.

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## 3. Attribution Requirements

ECMWF retains all Intellectual Property Rights and copyright over its data and software.  

ECMWF does not accept any liability whatsoever for any error or omission in the data and software, their availability, or for any loss or damage arising from their use.

When using or redistributing the Data Products, users must:

- Acknowledge (attribute) ECMWF as the source;
- Cite relevant publications, digital object identifiers (DOIs), or dataset identifiers where available;
- Include a reference to the CC BY 4.0 License;
- Where applicable, indicate clearly if the material has been modified and indicate previous modifications.

Recommended attribution information/wording for data products can be found on this web site:

https://apps.ecmwf.int/datasets/licences/openifshub/

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## 4. Delineation of Materials

For the avoidance of doubt:

- Materials primarily intended for execution, modification, or integration as software are classified as Software and are subject to the Apache 2.0 License.
- Materials primarily consisting of observational, simulated, or derived scientific data are classified as Data Products and are subject to CC BY 4.0.
- Where a file includes an explicit license notice, that notice shall prevail.

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## 5. Third-Party Content

Any third-party software, libraries, or data included in this repository remain subject to their respective licensing terms. Users are responsible for ensuring compliance with those terms.