Characterisation of discolouration plumes resulting from submarine volcanism using remote sensing techniques between 2000 and 2018

There’s still a poor understanding of how submarine volcanism works, although the majority of Earth’s volcanic activity happen in submarine context, forming new crust and ejection large amounts of material into the ocean.

This type of eruption has associated risks such as tsunamis and problems with shipping and air traffic, and is a source of natural pollution - gases such as sulphur and particulates are released into the atmosphere - hence the need for monitoring. Also, the study of submarine volcanic products will help understand in more detail how these volcanic processes evolve. Due to the remote location of submarine volcanoes, the use of remote sensing and earth observation techniques can be helpful in the monitoring process in order to mitigate the consequences of volcanic activity.

To answer this problem, a database of pre-registered submarine volcanic eruptions between 2000 and 2018 was created, with results stating 60 eruptions referring to 31 different volcanoes. A total of 450 satellite images were detected through observations of discoloration plumes associated with submarine events, and 82 of these images were subsequently selected for extraction of spectral signature, through what were considered to be the most representative images for the eruption in question, in order to proceed to the extraction of spectral signatures.

The spectral signature of the 263 sample points has similar characteristics within the different types of discoloration plumes (green coloration, brown coloration, and associated with pumice rafts) and can therefore be classified into several classes.

It can be concluded that the detection and differentiation of discoloration plumes associated with submarine volcanic events using remote sensing data can be accomplished effectively, confirming why remote sensing is an efficient and affordable technique for the regular detection, monitoring, and study of submarine volcanic eruptions in near-real time.