1. What's the state of play with Ruapehu, as we speak?
It's showing signs of slightly elevated unrest. There have been small earthquakes under the volcano, the heat underground has increased but the crater lake remains cold. So that gives the impression that there is hot gas trapped and pressure possibly building up. It's not unheard-of with Mt Ruapehu. What is key is that Ruapehu doesn't provide many precursory signs before an eruption. Which makes it difficult to monitor. But you have to be open-minded and keep the usual precautions.
2. From a scientific perspective it must be exciting?
It's a mix of scientific perspective with excitement. But it's almost a love-hate relationship. We are, as scientists, about as excited as we can be but people's safety remains the priority. But I almost prefer to focus on volcanoes that are not well behaved because I tend to like volcanoes that are a puzzle. That is one of the challenges.
3. Why do you do what you do?
I grew up in central France - Massif Central, near Clermont-Ferrand - and volcanoes surrounded us. I liked those funny mountains with the hole in the top. It was what I grew up with. But it is also the perfect triptych. You have science, nature and humans. It's also young science - there is so much we don't understand. I relish that. It also affects people positively. There are lots of places where people live around volcanoes because it's fertile land. It's a bit like sleeping in a house with a bad dog. You're never sure when it might bite you.
4. What is the most spectacular, volatile display of nature you've seen?
In Montserrat, in the Caribbean, there were two things that made me think how small we are. One is when there is a big eruption that has a big ash plume, it fills your horizon. The other is when you have hot gas and rock that can come from volcanoes that are totally silent. It's a fantastic visual display, but silent. It's eerie and it makes you step back and forget about everything. Which is a problem when you are doing the monitoring. You stand in awe but you have to get back to work. The capital city (Plymouth) is buried by a volcanic eruption. It's like a modern day Pompeii.
5. What and where is the highest point you've been - and what was the view like up there?
I was walking to the top of a volcano in South Peru called Misti. It's 5822 metres high. First, I mostly saw my feet because of exhaustion and altitude sickness. But once that got better and I got to the top it was like being on top of the world. It's immense. That is the only adequate word for that.
6. How does France look from here - do you have a yearning for your language and culture?
I have no hankering to be back in France. It's my country and I have a cultural attachment. But it looks far away to me. Distant and indiscriminate. Except during Rugby World Cups, that is. Home is where I live and right now that is New Zealand.
7. Describe your ideal habitat - what does it look like; feel like?
I'm not a city boy. I like places with wide landscapes and mountains. There has to be good food and wine there too. New Zealand is pretty close to the ideal habitat. The language being spoken? It doesn't matter. Smiles matter.
8. What French phrase makes your heart sing?
La mort d'une bonne action, c'est d'en parler.
It's more of a motto: The death of a good action is to talk about it. The reward of doing something is the bonus, not the reason for doing it. The simple thing, like lighting candles at home for your loved one - you don't do it for the reward. It's the same with what I do - I don't study volcanoes for a reward.
9. What erodes your sense of place or being?
Ignorance and unjustified hatred. I loathe it when people don't understand differences. Religious wars and crusades are a good example of that.
10. What, outside nature, diverts you?
I'm big on music. I play the guitar and I also like photography. I'm very visual. I like looking at things while there is music playing. Something soothing. There's something aesthetically pretty sweet mixed with adequate music.
11. When have you felt perilously close to the edge while going about your day?
I was standing by the edge of an acid crater lake in Costa Rica. The water was so acidic - about 0.5, which is about as bad as you can get - that it was degrading the ground I was standing on. It collapsed and I fell into the lake. I jumped out and stripped off and was washing myself - especially wanting to preserve the most vital parts of my body - with water and I heard these huge cheers. I looked up and there were about 200 tourists with binoculars and cameras laughing and cheering.
12. What staggers you most about the landscape in New Zealand - and what is the greatest threat to it?
The biggest threat may not be the most worrying. What staggers me most is the underlying power of dormant volcanoes. It's like a fancy sports car on idle. It's more impressive when it's idling than when it's going fast - when it's not displaying its speed but displaying its potential. When I was diving with sharks, it's the same thing. A slow shark is more impressive than a flying beast. Taupo to me is a silent reminder that we are so small in this big blue ball that is the earth.