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While the above products are free, you still need to check the licence for their use - you should find licence details with the products themselves. 

Free data are also available through the Copernicus Climate Change and Atmosphere Monitoring

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Services 

 If you want to explore the open and free of charge (see Copernicus Licence for details) data of the Copernicus Climate Change Service (C3S)  please have a look here: 

What data and charts are available through C3S (Copernicus Climate Change Service)?

 If you want to explore the open and free of charge (see Copernicus Licence for details) data of the Copernicus Atmosphere Monitoring Service (CAMS) please have a look here:

What data and charts are available through CAMS (Copernicus Atmosphere Monitoring Service)?

For details on datasets and questions please have a look at the Copernicus knowledge base and Copernicus User Support Forum Home.