Blast from past gets workshop

Science workshops and presentations at the Tongariro National Park Centre will mark 20 years since Mt Ruapehu erupted. Photo / Supplied

The 20-year anniversary of the Mt Ruapehu eruption will be marked by a range of science presentations at the Tongariro National Park Centre.

Scientists, emergency managers, conservation staff, iwi and university students will gather at Whakapapa Village from Friday for the Volcanic Science and Risk Management workshop.

It will feature a range of presentations and activities to reflect on two decades of progress in managing eruption hazards and risks in Tongariro National Park.

The event will also coincide with the 40th anniversary of the 1975 Ngauruhoe eruption and the 70th anniversary of the 1945 Ruapehu eruption.

Joint Centre for Disaster Research director David Johnston will discuss the social impacts of the volcanic hazards. It was an opportunity reflect on two decades' progress, he said. The centre is jointly run by Massey University and GNS Science.

Volcano information specialist at GNS Science, Brad Scott, said in spite of its picture postcard appearance Tongariro National Park was a highly active volcanic centre and it would be foolhardy to think of it simply as a benign outdoor playground.

"In 1954, Mt Ngauruhoe produced lava flows and in 1974 and 1975 it produced explosive eruptions," he said.

"Eruptions from Ruapehu in 1968, 1969, 1971, 1975, 1977, 1988 all produced lahars, as did the 1995-96 eruptions.

"More recently there was the major breakout lahar from the Crater Lake in 2007, which was more hazardous than the 1953 Tangiwai Railway disaster event.

"Then in 2012 there was an eruption episode from Te Maari craters on Mt Tongariro, which closed the popular Tongariro Alpine Crossing track for seven months."

The central North Island volcanoes are now being monitored with seismographs, GPS and web cameras placed throughout the National Park by the EQC-funded GeoNet project, keeping a close watch on the volcanic pulse of the area.

Volcanic Technical Advisor at the Department of Conservation, Harry Keys, said sudden volcanic events may still pose serious risks to people close to the active vents.

But the lessons of the past two decades had led to huge improvements in ability to manage volcanic risks, he said.