US: Oregon State University (OSU) scientists have discovered how to pinpoint the time and place of underwater volcanic eruptions using satellite images. Volcanic eruptions on the ocean floor can spew large amounts of pumice and fine particles, as well as hot water that brings nutrients to the surface, resulting in plumes of algae. The plumes are picked up as shades of green in satellite images.
"Some volcanic eruptions take place hundreds of feet below water and show no changes to the sea surface to the naked eye. It's amazing an orbiting satellite can detect color changes that indicate an eruption has taken place. Many times you can't spot an eruption if you were floating over it in a boat,” said Robert O'Malley, an OSU research assistant in botany and plant pathology in OSU's College of Agricultural Sciences. "Satellite measurements of the planet are made every day so this new method provides another tool for spotting these dramatic events that affect life in the oceans,” said Mike Behrenfeld, an OSU expert in marine algae. O'Malley and Behrenfeld developed a process for analysing low-resolution images to show evidence of eruptions, which can extend over thousands of square miles, by matching five known eruptions with data from NASA satellites.
Source: Oregon state edu