I. Introduction
In the big data era, scientific and social data could complement each other for enhanced data analysis and scientific discovery. For example, when thick fog and haze shroud some areas, we could see an increasing social engagement from the Web and online social media, either commenting or communicating the environmental situation. The event detected from the social data could alert and trigger analysis processes on scientific observation data, or confirm results from scientific analysis. The whole process could be accomplished using information technologies and infrastructure services. In the past decade, information infrastructures, such as spatial data and information infrastructure, e-science, and cyberinfrastructure, have been benefiting scientific communities and supporting scientific research. The infrastructures could be used to exploit the big data including social data.