A geologist ought to have a good grasp of geography. But the short walk from the voiceover studio in Soho to the Covent Garden hotel lobby in which we meet stumps Iain Stewart. He arrives apologetic, and slightly sheepish: "I am a geographer, after all," he says.
He can be forgiven for failing to navigate central London: the 41-year-old father of two juggles a typically demanding academic workload as a senior lecturer in geology at Plymouth University with a burgeoning career in television.
Dr Stewart specialises in Mediterranean earthquakes, but he explored the geology behind the food, art and culture of the region for the BBC in the first series of Journeys from the Centre of the Earth . He is working on a second series, and a new programme, The Truth about Climate Change , will air on BBC Four at the end of this month. "My role is the neutral scientist bridging experts and the person on the street," he says.
Although he was a child actor (in the TV series Huntingtower and alongside John Hannah in the panto Aladdin at 14), Dr Stewart's adult television fame is relatively recent. In 2002, he left Brunel University after 15 years lecturing in geology and geography to take an honorary position in Glasgow, which allowed him time to knock on doors and get the programme off the ground.
"We looked at why people go to the Med - for the food, art and culture - turned those reasons on their head and made them all to do with geology. The whole point of the series is pulling geology out from under the carpet. It's always there in the background, but the stories are about history and archaeology."
Dr Stewart, who is aware that geology suffers from a poor image, sees himself as an unofficial champion of the subject. Geology struggles with student numbers, and geologists should do more to tell people about their subject, he says.
"People were surprised when I said I was making a series about the subject. You get it all the time - it's seen as rocks and stones, but actually it's the stories they tell that are interesting. I find a lot of rocks tediously boring, but what they tell us about things that happened hundreds of millions of years ago is interesting. Once you pass the initial resistance, geology sells itself really."
Dr Stewart was conscious that fronting a TV series could open him up to academic criticism, but Journeys found favour with academics and the public alike - no mean feat.
"Academics got into what we were trying to do and that was great. They didn't tell us off for simplifying and dumbing down but said my enthusiasm for geology was really good. That was always in my mind, selling the totality of the subject, the idea of it - especially to parents whose children are thinking of studying it for three years and wondering whether they'll get a job at the end of it. Now we get parents wishing they could do a geology degree at Plymouth themselves," he says.
His television work means he is starting to get recognised. "I was on a train and ended up chatting to a woman who asked if I was 'the geologist from that programme'. She said at the end: 'I just want you to know that it was really good.' Then someone else piped up: 'Yes, I'll second that', which was great."
Being recognised by other geologists or academics, however, can be less welcome. Although some people at Plymouth, which he joined in 2004, affectionately call him the "media star", others see success as measured only by the research assessment exercise. "I still have to have four papers and get in research funding," he says. "There's nothing in the RAE that says go out and proselytise your subject and build recruits. They say: 'It's good, Iain, but are you still doing enough research?'"
Juggling teaching, research and television presenting is hard, but Dr Stewart clearly has passion enough for all three. And they marry well, he says. "A lot of the ideas for the programme come out of the research I'm doing or from going to conferences and talking to people," he says.
The idea of bringing together several disciplines, which is essential in television, is anathema to most academics but not to Dr Stewart. Before leaving Brunel, he organised a conference on environmental catastrophes in the Holocene. "It was interdisciplinary with archaeologists, anthropologists, biologists, geologists - that was great and gave me lots of ideas."
The television work also forces him to look beyond his own subject. "Last week we were in California talking about risk with anthropologists and historians. When I go back to teaching or to do research, it's impossible not to be influenced by some of those ideas."
Looking at a problem from different perspectives allows you to see more of it, Dr Stewart says. "There's no doubt that, academically, it's tricky going into other territories because you open yourself up for criticism for getting things wrong.
"The way to do it is to get people involved at the start and attack a problem together. The really interesting problems are in those 'shadow zones' that the main disciplines don't touch."
Dr Stewart's navigational skills may leave a lot to be desired, but he is undoubtedly an asset to a profession he is not keen to quit. "It's good to know there's a life beyond academia, but I love the variety of academic life. For now the telly work is a lark, but it probably wouldn't be if I were just being a presenter full time."
But the skills needed for television are not lost on his academic life.
"Being an academic is a performance. Everyone, whether consciously or not, thinks of a way through the material, a narrative, and students really respond to that. People who don't think of it as a performance either are deluding themselves or aren't that great. I suspect that those who love teaching like that aspect of performing and seeing the students really switch on."
I graduated from Strathclyde University
My first job was lecturer in geology, West London Institute of Higher Education (now Brunel University)
My main challenge is getting a geology sitcom into the research assessment exercise - seriously. Imagine the impact factor of that!
What I hate most is that 'look' you get when you mumble that you're a geologist. It's more than just a stone fetish, you know
In ten years , I will be over 50, recovered from turning 40, and hopefully still fire-juggling research, teaching and geo-telly
My favourite joke I had a tragic childhood. My parents never understood me. They were Japanese. (From the comedian Chic Murray)