Scientists from Japan have presented a new way to predict future volcanic eruptions. To do this, they analyze the color of the ocean around them.

The researchers explained that predicting volcanic eruptions is very difficult, as each volcano is unique. However, scientists can do this by indirect signs: increased seismic activity, temperature rise, expansion of magma basins, and the release of gases. A new study using satellite images has identified a new sign of a future eruption – a change in the color of the ocean.

Their idea is based on the fact that when underwater volcanoes erupt, the gases and compounds they release affect the composition of the surrounding water. For example, iron-rich water looks yellowish or brown, while aluminum and silicon make the water white. The problem was the systematic application of this information to make predictions. It is not easy to accurately measure these color changes.

A key forecasting tool is the Japan Space Agency’s (JAXA) satellite “Global Change Observation Mission – Climate” (GCOM-C). GCOM-C observes the ocean every 2-3 days at a resolution of 250 meters, giving scientists reliable data on the color change of the water. By combining GCOM-C imagery with eruption information from the Himawari-8 geostationary weather satellite, scientists were able to use the data and predict volcanic activity a month before it occurred.

One of the research’s major breakthroughs is the way it measures color accurately despite bright sunlight, which can distort its visible color. Scientists turned to other areas of research to find a solution – they developed a filter to combat distortion.