Volcanic Alert Levels
In New Zealand, we use a system of Volcanic Alert Levels to define the current status of each volcano. The alert levels range from 0 to 5.
Below there are two tables, one for the frequently active volcanoes like Ruapehu and White Island. The second one deals with the reawakening of dormant volcanoes like Mayor Island, Tarawera (in the Okataina Volcanic Centre) or Taupo. The alert levels are used by the public and responding agencies to set their response.
Frequently active cone volcanoes
- Ruapehu
- Tongariro-Ngauruhoe
- White Island
- Kermadec Islands
| Volcanic Alert Level | Indicative Phenomena | Volcano Status |
| 0 | Typical background surface activity; seismicity, deformation and heat flow at low levels. | Usual dormant or quiescent state. |
| 1 | Departure from typical background surface activity. | Signs of volcano unrest. |
| 2 | Onset of eruptive activity, accompanied by changes to monitored indicators. | Minor eruptive activity. |
| 3 | Increased vigour of ongoing activity and monitored indicators. Significant effects on volcano, possible effects beyond. | Significant local eruption in progress. |
| 4 | Significant change to ongoing activity and monitored indicators. Effects beyond volcano. | Hazardous local eruption in progress. |
| 5 | Hazardous large volcanic eruption in progress. | Large hazardous eruption in progress. |
Reawakening volcanoes
- Auckland
- Mayor Island
- Northland
- Okataina
- Rotorua
- Taranaki (Egmont volcano)
- Tarawera
- Taupo
| Volcanic Alert Level | Indicative Phenomena | Volcano Status |
| 0 | Typical background surface activity; seismicity, deformation and heat flow at low levels. | Usual dormant or quiescent state. |
| 1 | Apparent seismic, geodetic, thermal or other unrest indicators. | Initial signs of possible volcano unrest. No eruption threat. |
| 2 | Increase in number or intensity of unrest indicators (seismicity, deformation, heat flow, etc.). | Confirmation of volcano unrest. Eruption threat. |
| 3 | Minor steam eruptions. High-increasing trends of unrest indicators, significant effects on volcano, possibly beyond. | Minor eruptions commenced. Real possibility of hazardous eruptions. |
| 4 | Eruption of new magma. Sustained high levels of unrest indicators, significant effects beyond volcano. | Hazardous local eruption in progress. Large scale eruption now possible. |
| 5 | Destruction with major damage beyond active volcano. Significant risk over wider areas. | Large hazardous volcanic eruption in progress. |