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My ‘Climate Shock’ from a talk by Gernot Wagner

Sadly, the climate change rhetoric can sometimes feel a bit like the announcements at an airport; a little monotonous and irrelevant. Most of us have been guilty of tuning out, turning a blind eye and continuing with our life thinking the announcement isn’t really for us; we’re getting a different flight.

Sitting down for the hour long talk by Gernot Wagner at @Bristol on Tuesday evening was a little like hearing the last boarding call when you’re at the other end of the airport in a day dream. It was a shock.

‘Climate Shock’ was an hour of uncomfortable truths and mind boggling economics. As a scientist I am regularly exposed to the raw figures: Temperature in degrees, CO2 in parts per million, mean sea level increase. Never before had I been faced with the human implications of climate change in such stark and uncompromising terms.

The talk was run by Bristol Festival of Ideas and supported by the University of Bristol's Cabot Institute and slotted in comfortably with Bristol’s position as green capital of the Europe. Gernot Wagner walked us through his recent book ‘Climate shock’, co written with Martin Weitzman. At each turn of the page (or change of the slide) there was a new, fresh perspective on the climate change debate. Instead of seeing the problem and solution in science, Wagner saw it in economics.

With the cool detachment of a mathematician, Wagner attempted to communicate the uncertainties in our climate change predictions. Despite a considerable accumulation of knowledge, we are still powerless to predict the exact effect on our fragile planet. Wagner pointed out that, should temperatures rise by 6 degrees, the effects would be catastrophic. We are only a fraction of the way down the slippery slope of temperature increase and despite an escalation in extreme weather we still aren’t digging in our heels and climbing back up. With any other predictable, large-scale disasters we work tirelessly to insure and mitigate. Why, Wagner asked, are we not doing the same for climate change?


Using economics to convey the potential impacts, Wagner stated plainly that for every $1 we spend on CO2 producing activities, it is actually costing us $0.40 in future damages. We are already a planet in debt.

Wagner’s solution was atypical. Instead of sending us forth from the room as eco warriors, recycling like our lives depended on it, he emphasised a different message. He said the way to mitigate global warming is to harness the economic power of supply and demand.


His case study was Sweden. He introduced it with a single figure: $150.

This is the Swedish tax on each ton of CO2: as the price of CO2 went up, demand went down. Now, Wagner claimed, Sweden is nearly carbon neutral. His argument is that policy is the way to save the world- far more so than individual effort.

The realism of his suggestions made his talk fascinating. For the first time I not only grasped the terrifying toll that climate change is taking, but also felt hopeful that there might be a solution. While the solution might be unpopular in our short sighted capitalist society, it is absolutely essential for maintaining long term economic stability.

The moral of the story? The best investment you will ever make is in our planet.
This blog is written by Cabot Institute member Keri McNamara, a PhD student in the School of Earth Sciences at the University of Bristol.
Keri McNamara

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