Abstract
From weather forecasts to civil protection applications, earth observation data provide valuable input for policy-making towards a more sustainable society. During the last decade, several platforms and applications have been developed to store, process and analyse big and heterogeneous volumes of such data. Having thoroughly considered various techniques and approaches used to index, analyse and reason about these types of data, this paper proposes a hybrid knowledge graph and semantic-based approach for querying earth observation data sources. The proposed approach acts as a unified framework for diverse earth observation data sources, which does not only enhance data accessibility, but also enables the discovery of previously hidden knowledge and the extraction of meaningful insights.