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.
USGS4th of January 2023, 2 months ago
Anak Krakatau - 20230104/1713Z
Eruption with volcanic ash cloud at 1713 UTC (0013 local). Best estimate of ash-cloud top is around 2902 FT (907 M) above sea level or 2400 FT (750 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230104/1713Z
Eruption with volcanic ash cloud at 1713 UTC (0013 local). Best estimate of ash-cloud top is around 2902 FT (907 M) above sea level or 2400 FT (750 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230104/0809Z
Eruption with volcanic ash cloud at 0809 UTC (1509 local). Best estimate of ash-cloud top is around 10102 FT (3157 M) above sea level or 9600 FT (3000 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230104/0809Z
Eruption with volcanic ash cloud at 0809 UTC (1509 local). Best estimate of ash-cloud top is around 10102 FT (3157 M) above sea level or 9600 FT (3000 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewAnak Krakatau - 20230104/0710Z
Eruption with volcanic ash cloud at 0710 UTC (1410 local). Best estimate of ash-cloud top is around 822 FT (257 M) above sea level or 320 FT (100 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View3rd of January 2023, 2 months ago
Anak Krakatau - 20230103/0938Z
Eruption with volcanic ash cloud at 0938 UTC (1638 local). Best estimate of ash-cloud top is around 822 FT (257 M) above sea level or 320 FT (100 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View31st of December 2022, 2 months ago
Eruption with volcanic ash cloud at 0033 UTC (0733 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.
View28th of December 2022, 3 months ago
Eruption with volcanic ash cloud at 2335 UTC (0635 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.
View20th of December 2022, 3 months ago
Eruption with volcanic ash cloud at 2245 UTC (0545 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.
View19th of December 2022, 3 months ago
Eruption with volcanic ash cloud at 0858 UTC (1558 local). Best estimate of ash-cloud top is around 16563 FT (5176 M) above sea level or 4800 FT (1500 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewEruption with volcanic ash cloud at 0003 UTC (0703 local). Best estimate of ash-cloud top is around 14003 FT (4376 M) above sea level or 2240 FT (700 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View18th of December 2022, 3 months ago
Eruption with volcanic ash cloud at 2216 UTC (0516 local). Best estimate of ash-cloud top is around 13043 FT (4076 M) above sea level or 1280 FT (400 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewEruption with volcanic ash cloud at 0049 UTC (0749 local). Best estimate of ash-cloud top is around 14003 FT (4376 M) above sea level or 2240 FT (700 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
View17th of December 2022, 3 months ago
Eruption with volcanic ash cloud at 2323 UTC (0623 local). Best estimate of ash-cloud top is around 14323 FT (4476 M) above sea level or 2560 FT (800 M) above summit. May be higher than what can be observed clearly. Source of height data: ground observer.
ViewEruption with volcanic ash cloud at 2152 UTC (0452 local). Best estimate of ash-cloud top is around 12723 FT (3976 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.
