Eruption response an 'overreaction' - mayor

Taupo's mayor has criticised the response to Mt Tongariro's eruption this week, calling it an overreaction.

Thick grey smoke, gas and ash spewed 4km into the sky from Te Maari vent on the western side of the mountain during the unexpected eruption just before 1.30pm on Wednesday.

It is the same place where Tongariro erupted in August, for the first time in more than a century.

Flights were cancelled, a Civil Defence alert put out, a 3km exclusion zone has been set up around Mt Tongariro and The Department of Conservation closed its tracks within a 3km radius of the crater.

But Mayor Rick Cooper told Newstalk ZB the response an overreaction, saying that as a society we had become too precious.

Mt Tongariro was a live volcano, so small eruptions were a fact of life, he said.

"We have to live and learn to live with a live volcano. She does, from time to time, the beautiful woman, stamp her feet. Whilst we need to take all precautions we should not overreact," he told the radio station.

However, Mr Cooper told Newstalk ZB it was good to have the area's beauty promoted on the world stage.

Experts warn there is a high chance of Mt Tongariro erupting again, in the next week.

"The volcano is in a state of unrest," he said, "I definitely wouldn't say another eruption wasn't going to happen," GNS volcanologist Brad Scott.

DoC spokesman Bhrent Guys said staff would remain posted at the main entrances to the national park on the central plateau tomorrow to stop curious spectators getting too close and the Tongariro Crossing would remain closed for at least the next two more days.

Poor weather is preventing volcano experts from flying over Mt Tongariro to check gas levels.

Volcanologists were scheduled to conduct an aerial observation today to gather information about how much gas is being emitted by the volcano, but a thunderstorm has left low cloud over the area and the wrong wind direction have stopped it from going ahead.

They had planned to circle the plume taking measurements with gas sensors, to gather readings about sulphur dioxide and carbon dioxide levels, GNS Science duty volcanologist Nico Fournier said.

The information could give clues about any changes to the volcano.

"At the moment there's a north west wind so the plume is going back into the mountain. It's not looking very promising I'm afraid."