OccVis: a visual analytics system for occultation data

The FY-3C satellite returns more than 250,000 occultation data each year, each of which records high vertical resolution profiles of various climatic parameters in the range of 0-1000km above the Earth. These long-term, stable, and globally distributed observations can be used to improve climate modeling and analyze trends in spatial climate. However, traditional methods based on small samples meet challenges in analyzing the multi-dimensional occultation data in large volume. In this paper, we developed OccVis-a visual analytics system for multi-dimensional and multi-scale comparative analysis of occultation data. With a novel workflow, a series of data processing methods are proposed to support data correcting, patching, and clustering. Moreover, a matrix view with two modes is presented for overview, and a detail view along with time series view is provided for further analysis. Domain scientists can easily utilize our system to visually and interactively explore multivariable occultation data at different time and space scales. Finally, we conduct case studies in climate modeling of ionosphere and obtain several preliminary results to demonstrate the usage and effectiveness of our system.