Nature was testing the Ski Area eruption alarms on Mt Ruapehu Sunday morning.
For the Eruption Detection System (EDS) to go off two things are needed. The first is earthquakes – quite a few reported over by Turangi on Sunday that are popping into the Ruapehu part of the system, the second are strong wind gusts that set off the airwave detectors. For the alarm to sound, the system needs to see earthquakes and airwaves together – like the perfect storm mimicking an eruption.
On Sunday morning Mt Ruapehu had both factors and as a result, EDS alarms have sounded. RAL can confirm that these were false positives, and there is no cause for concern at this time. Thank you to those on the mountain for staying indoors and out of danger until you received the stand-down message.
Alarms from the Eruption Detection System should always be treated as real. The public are urged to always follow instructions from the alarm system and from mountain staff.