Sulfur Dioxide Leaks from Kilauea

Hawaii’s Kilauea has been erupting continuously since 1983, but in late April and early May 2018 the volcanic eruption took a dangerous new turn. On May 3, 2018, several new fissures cracked open the land surface in the Leilani Estates subdivision, leaking gases and spewing fountains of lava. By May 7, 2018, slow-moving lava flows had consumed 35 homes in that community of 1,500 people.

This series of images, created using data from the Ozone Mapping Profiler Suite (OMPS) sensor on the Suomi National Polar-orbiting Partnership (NPP) satellite, shows elevated concentrations of sulfur dioxide on May 5, 2018, a few days after the new fissures opened up. Sulfur dioxide is a toxic gas that occurs naturally in magma. When magma is deep underground, the gas remains dissolved because of the high pressure. However, pressure diminishes as magma rises toward the surface, and gas comes out of solution forming bubbles in the liquid magma.

“The process is similar to what happens when a bottle of soda is opened,” explained Ashley Davies, a volcanologist at NASA’s Jet Propulsion Laboratory. “The bubbles of sulfur dioxide and other volatiles, including water and carbon dioxide, begin to rise through the liquid magma and concentrate in the magma closest to the surface, so the first lava to erupt is often the most volatile-rich. There’s usually an increase in sulfur dioxide output right before lava reaches the surface, as the gas escapes from the ascending magma.”

See NASA Earth Observatory