Most comedians don't have any use for the word August in their vocabulary, Matt Winning tells me. When it comes to describing the eighth month of the year most prefer to use the word Edinburgh.

"I have been here seven years in a row now," he says. "I've not had an August for seven years. I've had an Edinburgh."

We are sitting in a makeshift cafe in the Cowgate. Half an hour ago he was onstage in an upstairs room in the Opium nightclub across the road as part of the Edinburgh Free Fringe, where he nested a stand-up routine about Bruce Willis, R&B stars, fruit-based technology companies, his favourite food (corn on the cob as it happens) and the looming danger to life on earth caused by climate change into a futuristic comedy narrative which explores how his own Fringe show in 2016 will change the world.

Now we are drinking coffee and discussing his day job as an economist working on environmental policy and the prospect of environmental disaster.

But for the moment he's discussing why he's here and why here – Edinburgh and the Fringe – still matters

"You learn a lot in Edinburgh. It's the most important month. For a comedian it's still the key absolutely. There's probably a younger generation, people 10 years younger than me and they can probably go on YouTube and do it. But anyone as old as me …"

He is the grand age of 31 by the way.

By day Winning, who's originally from Kilbarchan, is a research associate in environmental economics at University College London. By night – and for the next couple of weeks – he's a stand-up comedian. Given that he's constantly gigging and it takes him 10 months to write a show like his current one Ragnarok (the end of the world in Norse mythology of course), you wonder where he finds the time. The answer is, he tells me, writing the comedy on his lunch breaks.

Fortunately, working in academia, it's a bit easier getting a month off at a time. "My girlfriend is not very happy because it means we only get to go away for one week a year."

He's been on the comedy circuit since he was 24 when he did Viv Gee's stand-up evening class at Strathclyde University while studying for a PHD there.

"A lot of comedians will say you can't teach people to do comedy. I think it is teaching people to have the confidence to go on stage for the first time. That's really all it's teaching you because you're still terrible at the end of those six weeks."

How was your first gig? "I hadn't told anyone at all. I don't even think I told my parents I was doing the course. I went on and did it and I got heckled by two big Glaswegian guys at the back of the room. I think I was the only guy who got heckled. I talked about breaking a bone. They said 'oh, was it your funny bone?' Their joke was funnier than my set. I had no idea how to deal with this and panicked. But maybe that pushed me to do it more. I was like 'next time …'"

That was in 2008 and he's been a regular on the comedy circuit ever since. "I never really wanted to be a performer, but once you get better and it goes well it gets a bit addictive."

He even met his girlfriend Jessica at The Stand in Glasgow. She was selling tickets at the time. "I would go down pretty much every night to see her. I was even performing sometimes." Now she takes the photographs for his posters.

Is he ambitious as a comedian? "A bit. I see people who are very ambitious and I don't like most of them. But I also feel you've got to have some self-belief."

He'd like to be able to do bigger shows and maybe even have his own fans. The economist in him starts doing some calculations when I ask him to quantify that desire. "100 people a day for 20 days? I'd like to have between two and 4,000 fans in the country."

What's intriguing is the contrast between the stand-up and the day job, which couldn't be more serious.

Winning did a law and economics degree at Edinburgh University, where he became interested in environmental issues, graduating in 2006. After a year working as an intern in an investment bank (a year before the crash, he points out), he was offered a PHD at Strathclyde to study the macroeconomics of marine energy in Scotland. This was a challenge. "It's very hard to do when there isn't a marine energy sector in Scotland."

These days he crunches numbers on government proposals for emission reductions in an attempt to help them meet their targets at the least cost possible. What I want to know is, I tell him, given that he has an inside track on climate change, how has he retained his sense of humour in the face of the evidence that as a species we have screwed the planet right up?

"It's depressing if you think about it too much. But I work with some amazing people and their entire passion in life is trying to help to solve this. But it can be overwhelming at times. It's such a large problem."

How worried should we be, Matt? "Very worried. Extremely worried. But then most of us will be dead by the time it really kicks in. By the end of the century the world is going to be a different place, without a doubt. We've got maybe 10 to 15 years left to start really making huge reductions in emissions. The UK is committed to an 80 per cent reduction in emissions on 1990s levels and we need pretty much every country in the world to be doing that for us to have a decent chance of the world continuing roughly as normal."

The problem, though, he points out, is that climate change is a slow, complex process and we're as a species not attuned to taking the long view. But there has already been an increase in droughts and the subsequent rise in migration. (Some have linked the current war in Syria to pressures caused by climate change.)

How bad will it get if we don't' take adequate action? "It could potentially be anything from the world becoming a lot hotter and there being a lot more diseases and more people moving to Scotland to ice caps melting, sea levels rising and countries disappearing. It's anywhere from bad to worst case scenario, in my opinion."

And yet in a world where government ministers called Michael Gove (or now ex-government ministers called Michael Gove) can dismiss the input of experts, climate-change deniers are still vocal in their dismissal of such fears.

"It's dangerous rhetoric," he says. "It's not a belief, it's science. If you don't believe in climate change it's like saying 'I don't believe in gravity.' It's still happening. So giving it air as a belief in the media is dangerous."

The key is keeping it in the public eye, he says. Comedy might help with that. But it's hard he admits to find the humour in Armageddon-type scenarios. But he is trying with Ragnarok.

"I was hoping to write a show that was more about it but I found it difficult so then it became a show about how difficult it is to write a show about."

Is it too scary to joke about? "Nothing's too difficult to joke about." He points at fellow comedian Bridget Christie tackling the subject of female genital mutilation. He just worries that when it comes to climate change he's too close to it though.

Actually I think now that Winning's an Edinburgh veteran this should be his next target, a dedicated show about this biggest of big subjects. He has all the numbers at his fingertips after all. And he'd better get a move on. If his calculations are right we've only got 34 years to go before it's too late anyway.

Matt Winning: Ragnarok is at Opium, Cowgate, Edinburgh at 3.45pm each day until August 27.