Satellite-based remote sensing techniques for detecting pumice rafts
Abstract
Pumice rafts are accumulations of floating volcanic pumice on the ocean surface, typically generated by submarine eruptions. They can persist for months and drift over long distances, posing threats to maritime navigation, port operations, and marine ecosystems. Owing to its wide spatial coverage, repeated observations, and multispectral capability, satellite remote sensing has become an important tool for monitoring of pumice rafts. This review compiles satellite-documented pumice rafts events since 2001 and summarizes the sensors and products used in these studies. It clarifies the principles of four commonly used detection methods including visual interpretation, threshold-based methods, pumice index–based methods, and machine-learning methods and compares their strengths, limitations, application scenarios, and reported extraction performance. It also discusses several remaining issues, including fragmented data sources, inconsistent methodological frameworks, limited quantitative retrieval capacity, and reduced robustness under complex environmental conditions. Finally, this review outlines future research directions and provides a methodological reference for more standardized, automated, and operational satellite remote sensing of pumice rafts, with relevance to volcanic-marine hazard response and ocean safety management.