Alert Level has been established by Center of Vulcanology and Mitigation Geology Disaster. The eruption was confirmed by the Indonesian government's Centre for Vulcanology and Geological Hazard Mitigation. Results were reported to the Rabaul Vulcanology Observatory. The study of volcanoes is called volcanology, sometimes spelled "vulcanology". It is included on the World Heritage List especially because of its worth for vulcanology. Indonesia's vulcanology agency warned that flights around Yogyakarta may be disrupted.