Distributed Fusion of Heterogeneous Remote Sensing and Social Media Data: A Review and New Developments

Abstract

Despite the wide availability of remote sensing big data from numerous different Earth Observation (EO) instruments, the limitations in the spatial and temporal resolution of such EO sensors (as well as atmospheric opacity and other kinds of interferers) have led to many situations in which using only remote sensing data cannot fully meet the requirements of applications in which a (near) real-time response is needed. Examples of these applications include floods, earthquakes, and other kinds of natural disasters, such as typhoons. To address this issue, social media data have gradually been adopted to fill possible gaps in the analysis when remote sensing data are lacking or incomplete. In this case, the fusion of heterogeneous big data streams from multiple data sources introduces significant demands from a computational viewpoint. In order to meet these challenges, distributed computing is increasingly viewed as a feasible solution to parallelize the analysis of massive data coming from different sources (e.g., remote sensing and social media data). In this article, we provide an overview of available and new distributed strategies to address the computational challenges brought by massive heterogeneous data processing and fusion for real-time environmental monitoring and decision-making. The 2013 Boulder (Colorado) flood event is taken as a case study to evaluate several new distributed data fusion frameworks. Experimental results demonstrate that the proposed distributed frameworks are suitable in terms of response time and computational requirements for fusing large-volume heterogeneous data sources.