Changes of land systems are largely a consequence of human decision making at multiple scales, from local land management to national land use planning and global trade agreements. Improved understanding of the status, trend, and consequences of land changes is relevant to the engagement of Land System Science (LSS) in transformations for sustainability. While remote sensing has been a major tool for documenting land cover change, new opportunities are emerging to understand land as a socio-ecological system by integrating crowd-sourced social sensing data (e.g. through mobile technologies). Increased access to remote sensing time series and social sensing data are improving mapping of land and providing new information on the coupled social-ecological system for better land governance. Given advances in data availability and machine learning algorithms, land mapping efforts have evolved to more sophisticated analysis strategies. In addition, the emergence of planetary-scale geospatial analysis platforms facilitates regional and global land change monitoring in a rapid, scalable, and convenient way. This review aims to document current status and prospects on data, algorithms, and processing platforms in the era of ‘Big Earth Data’, providing examples of how it can contribute to LSS at the interface of normative and policy concerns, including those in support of internationally agreed environmental goals and land governance.