Volcano Watch  is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and affiliates.  Scientists from the U.S. Geological Survey and Ministerio de Medio Ambiente y Recursos Naturales collect a sediment core from the Las Ninfas volcanic crater in El Salvador on March 23, 2026, searching for volcanic ash deposits. USGS photo by M. Zoeller. El Salvador is the smallest country in Central America, sitting on the Pacific coast and measuring slightly larger than all the Hawaiian Islands combined.  However, the eight main Hawaiian Islands are comprised of only 15 volcanoes above sea level; El Salvador, on the other hand, has over 200! And that’s with a population of about 6 million people, about four times as many as Hawaii. There are numerous volcanoes in El Salvador because it sits along the Central American volcanic arc, rather than atop a hotspot like Hawaii.…