The volcanic alert level for Whakaari/White Island has been lowered to two following a small eruption last week, though scientists advise that the risk of further activity remains.
GNS Science, through its GeoNet monitoring service, announced on Monday that after a period of heightened activity, eruptive behaviour had ceased for the time being. However, the Aviation Colour Code remains at Orange, signifying that the likelihood of further ash emissions that could affect aircraft is still elevated.
The decision to lower the alert level came after monitoring equipment, including webcams pointed at the active crater, detected no further ash since the eruption last week. The move signifies a shift from a minor eruption to a state of 'moderate to heightened unrest'.
Alert level lowered but risk remains
Earth Sciences New Zealand Duty Volcanologist Agnes Mazot said that while the immediate eruptive phase appears to be over, the volcano's state is still far from normal. She stressed that the situation could change rapidly.
While eruptive activity has ceased for now, volcanic activity could re-escalate with little or no warning.
Any new explosive activity would likely be concentrated on the crater floor and the immediate area around the island. GeoNet has stated that ashfall reaching the mainland Bay of Plenty coast remains unlikely at this stage. An observation flight will be conducted as soon as weather permits to gather more detailed information.
The recent eruption was the latest event in a month of increased volcanic unrest at Whakaari. The alert level had been raised twice since the beginning of March, keeping communities along the Eastern Bay of Plenty on watch. Last week, Volcanic Duty Officer Steven Sherburn noted that it would not be unusual for people on the mainland to see steam plumes, which may occasionally appear darker if they contain some ash, and that this pattern could persist for several weeks.
A history of tragedy and caution
The cautious approach from scientists and authorities is rooted in the tragic events of December 9, 2019. On that day, a sudden, explosive eruption occurred while 47 people, mostly international tourists, were on the island. The eruption claimed 22 lives and left dozens more with severe and life-altering injuries, making it New Zealand's deadliest volcanic event in over a century.
In the aftermath, access to the island was completely restricted, and the once-thriving tourist operations ceased. The event triggered a comprehensive review of adventure tourism safety regulations in New Zealand and resulted in a major prosecution by WorkSafe NZ against several parties, including tour operators and GNS Science itself, for safety failings. The ongoing legal and safety repercussions have fundamentally changed how Whakaari is managed and monitored.
Before the 2019 disaster, Whakaari was a popular visitor destination, with guided tours allowing thousands of people each year to walk on the crater floor of an active marine volcano. This provided a significant economic boost to the nearby town of Whakatāne, the main departure point for tours. The loss of this tourism has had a lasting impact on the local economy.
Understanding the alert systems
New Zealand's Volcanic Alert Level (VAL) system, managed by GeoNet, ranges from 0 (No volcanic unrest) to 5 (Major volcanic eruption). The current Level 2 indicates 'moderate to heightened volcanic unrest', with potential for eruption hazards and an acknowledgement that eruptions can occur with little or no warning. Level 3, which was in place during last week's minor eruption, signifies a 'minor volcanic eruption'.
The separate Aviation Colour Code system is crucial for the airline industry. Ash clouds pose a severe danger to aircraft, as the fine particles can melt in jet engines and cause them to fail. The current 'Orange' code warns pilots that a volcano is showing heightened unrest with an increased chance of eruption, or that an eruption is underway with minor or no ash. The highest level is 'Red'.
Whakaari, located 48 kilometres off the coast, is New Zealand's most active cone volcano and has been in a near-constant state of activity for decades. While the recent activity has been minor, it serves as a powerful reminder of the island's inherent volatility.
Scientists will continue to use a network of cameras and seismic sensors to monitor the volcano around the clock. The community remains watchful, aware of the power that lies just off their shores. As monitoring continues, authorities have reaffirmed that the island remains a 'no-go' zone, with the lessons from 2019 shaping every decision.
