White Island is putting on a spectacular show at the moment, and scientists are warning that last time it displayed such vigorous volcanic activity eruptions quickly followed.
So does it pose a threat to visitors to the island or those on the mainland?
GNS volcanologist Brad Scott says hydrothermal activity on the island has been increasing since January 13, only a week after GNS Science reported the volcano was quietening down.
"Especially over the last three or four days it's got really quite vigorous," he told Firstline this morning.
White Island erupted in 2000 following signs of increased activity, and Mr Scott puts the chances of that happening now at 50-50.
"This could carry on increasing and lead to an eruption – on the other hand it could just cool down and go away. The indications at the moment are not strong either way, unfortunately."
White Island, 48km off the Bay of Plenty coast, poses no threat to the mainland if it does erupt, says Mr Scott.
"That's one of the great urban myths… when we look at the geological record and the seabed cores and stuff like that, there's absolutely nothing to indicate in the last 10 or 15,000 years that White Island has affected the mainland.
"Volcanic gas can reach the mainland, a little bit of volcanic ash – about the same as pollen on your car – has reached the mainland in the last 20 or 30 years during eruptions, but there's absolutely nothing to indicate a significant issue for the Bay of Plenty coast at all."
Patrick O'Sullivan from White Island Tours told the New Zealand Herald this morning that the threat of an eruption is good for business.
''(The increased activity) is definitely giving it a lot more attention, we're seeing a lot of hits to our website," he told the paper.
"It's just a great opportunity for people to get to a volcano that is so accessible, because there's not that many around the world where you can just pull up and hop right on."
Mr Scott says visitors have to appreciate there is a degree of risk in visiting an active volcano.
"As long as people are aware of it and they understand the risk, you can visit the place – but at other times maybe you shouldn't be visiting there.
"At the moment it's sort of putting its hand up and saying, 'Hey, I'm thinking of doing something,' and that's just increasing the level of risk."
Bay of Plenty Civil Defence has also warned of the risk, and is keeping local tour operators informed.