Submarine volcanism from satellite imagery

The majority of the Earth's volcanoes are on the ocean floor, but direct observations of submarine eruptions are very rare. This means that fundamental characteristics of submarine volcanism, including eruption repeat times, remain largely unknown. Although only a small subset of submarine events will result in changes at the ocean surface, many of these are detectable in satellite imagery. Localised ocean colour change occurs both when erupted material is sufficiently shallow, and in the period after an eruption, when volcanic material may stimulate algal blooms (e.g., Urai & Machida, 2005). Eruptions that breach the ocean surface can produce distinctive sub-aerial plumes dominated by steam (e.g., Carey et al., 2014), as well as new, often transient, land. The most distinctive satellite signals are produced by pumice rafts, which can persist for long periods of time, travel great distances and pose a hazard to shipping (Mantas et al., 2011). Past observations of submarine eruptions from satellite imagery have required the manual analysis of satellite images and are limited to individual case studies. This project will develop a systematic approach to detecting submarine volcanic events from global satellite data sets.