The Australian Geoscience Data Cube - foundations and lessons learned

Abstract

The Australian Geoscience Data Cube (AGDC) aims to realise the full potential of Earth observation data holdings by addressing the Big Data challenges of volume, velocity, and variety that otherwise limit the usefulness of Earth observation data. There have been several iterations and AGDC version 2 is a major advance on previous work. The foundations and core components of the data cube are: (1) data preparation, including geometric and spectral radiometric corrections to Earth observation data to produce standardised surface reflectance measurements that support time-series analysis, and collection management systems which track the provenance each data cube product and formalise re-processing decisions; (2) the software environment used to manage and interact with the data, including a minimal relational model that uses ‘not-only-SQL’ to simplify the process of adding new datasets to the data cube, or to simply ‘reference’ external datasets; and (3) the supporting, integrated, high performance computing - high performance data environment (HPC-HPD) provided by the Australian National Computational Infrastructure which supports both large scale analysis within the NCI, and direct access to data using standards-based web services. A growing number of exemplars demonstrate that the data cube approach allows analysts to extract rich new information from Earth observation time series, including through new methods that draw on the full spatial and temporal coverage of the Earth observation archives. To enable easy-uptake of the AGDC, and to facilitate future cooperative development, our code is developed under an open-source, Apache License, Version 2.0. This open-source approach is enabling other organisations, including the Committee on Earth Observing Satellites (CEOS), to explore the use of similar data cubes in developing countries.