VONA stands for Volcano Observatory Notice for Aviation. It issues reports for changes, both increases and decreases, in volcanic activities, providing a description on the nature of the unrest or eruption, potential or current hazards as well as likely outcomes. See the following link (USGS) for further details. The Center for Volcanology and Geological Hazard Mitigation (CVGHM) under the Geological Agency of the Indonesian Ministry of Energy and Mineral Resources produced VONA's reports based on analysis of data from the agency's monitoring networks as well as from direct observations. VONA's alert levels are color-coded to indicate the different types of notifications addressing specific informative needs. The reports are disseminated via email to national and international stakeholders in the aviation sector. Other interested parties can avail of them through email subscription. All notifications are publicly available online.
USGS27th of January 2023, 1 week ago
Eruption with volcanic ash cloud at 0102 UTC (0802 local). Best estimate of ash-cloud top is around 13363 FT (4176 M) above sea level or 1600 FT (500 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View26th of January 2023, 1 week ago
Eruption with volcanic ash cloud at 2234 UTC (0534 local). Best estimate of ash-cloud top is around 13683 FT (4276 M) above sea level or 1920 FT (600 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230126/0032Z
Eruption with volcanic ash cloud at 0032 UTC (0732 local). Best estimate of ash-cloud top is around 2102 FT (657 M) above sea level or 1600 FT (500 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View25th of January 2023, 1 week ago
Anak Krakatau - 20230125/2333Z
Eruption with volcanic ash cloud at 2333 UTC (0633 local). Best estimate of ash-cloud top is around 1462 FT (457 M) above sea level or 960 FT (300 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230125/2212Z
Eruption with volcanic ash cloud at 2212 UTC (0512 local). Best estimate of ash-cloud top is around 1462 FT (457 M) above sea level or 960 FT (300 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View24th of January 2023, 2 weeks ago
Eruption with volcanic ash cloud at 2240 UTC (0540 local). Best estimate of ash-cloud top is around 13683 FT (4276 M) above sea level or 1920 FT (600 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewEruption with volcanic ash cloud at 2150 UTC (0450 local). Best estimate of ash-cloud top is around 13363 FT (4176 M) above sea level or 1600 FT (500 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230124/1257Z
Eruption with volcanic ash cloud at 1257 UTC (1957 local). Best estimate of ash-cloud top is around 1462 FT (457 M) above sea level or 960 FT (300 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewVolcano is in normal, non-eruptive state, or, after a change from a higher level: Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.
Volcano is experiencing signs of elevated unrest above known background levels, or, after a change from higher level: Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.
Volcano is exhibiting heightened unrest with increased likelihood of eruption with column height below 6000 meter above sea level.
Eruption is forecast to be imminent with significant emission of ash with column height above 6000 meter above sea level.
