Abstract
Cloud computing in Earth System Sciences (ESS) has become inevitable, due to the ever-growing amounts of data and the need for cross-disciplinary collaboration. Cloud computing has therefore been an evolving field throughout the last years, leading to a fragmented landscape of offerings where no consolidation has taken place yet. Thus, users are confronted with a wide spectrum of solutions often aiming at the same goal. However, user surveys show strong interest in moving from traditional workflows to cloud processing in ESS. Nevertheless, there are some major obstacles that haven’t been solved yet. Users report that the steep learning curve, high degree of fragmentation and especially the lack of interoperability between platforms, data and workflows is hindering their transition (Wagemann et al. 2021, DiLeo et al. 2024). To reduce this complexity and improve interoperability, the Open Geospatial Consortium's GeoDataCube Application Programming Interface (OGC GDC API) aims at harmonizing existing solutions to access and process data cubes (multi-dimensional data structures organized along multiple dimensions) on cloud platforms by working towards defining a standardized API. The suite of standardized OGC APIs (e.g. OGC API Coverages, OGC API Processes) covers a large part of the functionality. At the same time, openEO offers a well defined API for cloud processing in ESS. Accordingly, the main challenges are (a) aligning the solutions where identical functionalities are solved in different ways and (b) identifying the gaps in data cube functionalities from selective data access to producing interoperable results without intermediate downloads (e.g. combining data access and processing, tracing of provenance). This talk will present the current status of the OGC GDC API as advanced in the OGC Testbed-20, and the OGC GDC Standard Working Group. The core capabilities of OGC GDC API will be presented, which include combining data access and analysis, allowing access to different data sets in the form of data cubes with the possibility of filtering, subsetting and aggregating (reshaping the original data cube to custom parameters), and tracing provenance of results. The OGC GDC API draft consists of a set of modular profiles which allow a large range of functionality when implemented together (GDC API Core, Partial Access, Resampled Access, GDC Data Processing). The functionality will be showcased through a use case which is calculating the Vegetation Health Index by combining different data sources, such as optical satellite data and meteorological data and highlighting the current status of interoperability between implementations of the OGC GDC API. To open the outlook into the future, the results of the usability testing carried out in the Testbed-20 will be presented. Finally, we want to open the discussion for defining the future directions of the OGC GDC API and its role in the ecosystem of standardized ESS cloud computing.