If we continue with our reckless burning of fossil fuels, there will be widespread war and conflict this century, warns Lord Nicholas Stern, the distinguished chairman of the Grantham Institute on climate change, whilst speaking before a packed auditorium at the London School of Economics on Wednesday.
Former chief economist at the World Bank, and author of a seminal paper on the economics of climate change, Stern certainly understands a thing or two about risk:
"Two centuries of scientific enquiry indicate that the risks from a changing climate over the next hundred years are immense. There is a strong possibility that hundreds of millions of people would have to move. History tells us that this carries serious risks of severe and extended conflict."
"So, the science has given us the most difficult problem we could possibly have," argues Stern. And, since his landmark paper came out nearly 10 years ago:
"The science has got riskier, emissions have gone up faster than we thought. And, the effects are coming through, like the melting of the Arctic ice, much quicker than we imagined. Both the science and the risks look far more worrying."
In order to come up with a solution, Stern says that it is critical to appreciate the scale of the problem.
Each ton of carbon dioxide that it emitted into our atmosphere stays there for thousands of years. And, owing to the accumulative effect of burning oil, gas and coal since the dawn of the Industrial Age, the amount of carbon dioxide in our atmosphere has now shot past record highs. CO2 acts like giant blanket heating up the planet.
World temperatures have already risen by nearly one degree celsius, and according to the United Nations, our world is currently on track to warm by more than four degrees celsius by the turn of this century.
A 4C temperature rise will usher in changes not seen since the last Ice Age.
"So, the stakes that we are playing for are immense," says Stern.
Five years ago, world leaders promised to limit the warming of our planet to two degrees celsius. But, according to the UN, we are set to race past that mark within the next thirty years.
In a bid to temper such a destructive fate, Stern argues that we have to embrace some radical changes, the first of which is seriously curbing our use of fossil fuels:
"We currently emit about 50 billion tons of carbon dioxide every year. We have to cut world emissions from 50 billion tons to 20 billion tones over the 35 years to stay under the two degrees celsius target. We then have to go to zero by the end of the century."
Although, this is a herculean task, Stern says that "we have to move very quickly if we're going to give ourselves any reasonable chance."
Speaking less than six months before world leaders gather in Paris to strike a make-or-break deal to rein in global warming, Stern argues that "research and development must be at the heart of economic policy in dealing with climate change:"
Earlier this week, Stern, together with a group of prominent British scientists and businessmen, launched the Global Apollo Program. Named after the $150 billion 1960's project to put a man on a moon, the group argue that if the same amount of money was spent today, we can bend the curve of catastrophic climate change:
"We're asking for about $15 billion a year from around the world, which is peanuts, to invest in fostering new renewable energy technologies."
In fact, it will cost big countries as little as 0.02% of their annual GDP, and such money will go into a global kitty to finance R&D for more innovative forms of clean energy. The aim is to make renewable energy cheaper than coal within the next 10 years.
Coal is the most polluting of the fossil fuels. But, as it is one the cheapest, it currently fires nearly half of the world's electricity. But, according to Stern:
"If anyone ever says to you that coal is cheap, don't let them finish the sentence because it's not. A tone of coal costs around $50, but you have to multiply it by 1.9 to get the cost of the CO2 that is emitted so that takes you up to $100 a tone. And, then add at least another $100 for the cost of air pollution."
And, whilst the scale of the problem can seem overwhelming, Stern argues that one starts to get "cheerful when you realize that these changes are accompanied with huge opportunities for immense structural change."
As half of the globe's population now live in cities, with that number going up to two thirds by the middle of the century, the urban centers of the world need to become low carbon hubs:
"This scale of change only happens once in history and, we're going to have to make some pretty big investments in our cities. And, we make either make these investments well, or we can made them badly. If we transition well, then we'll cut the lion's share of our emissions."
According to a report which Stern published last year together with a group of former heads of state, this global transition will require around $90 trillion of investment over the next 15 years.
"So, if we look at this as a story of growth, innovation and change, we become far less pessimistic. It's a fascinating time to be alive because this level of change is fundamental to the future of us all. But, it's also worrying because if we make a mess of it the consequences will be very difficult to extricate ourselves from."
Less than six months before that critical summit kicks off in Paris, Stern says that the level of ambition needs to be raised:
"National contributions from Paris are coming in around 55 to 60 billion tons of carbon. On any reasonable calculation, we shouldn't be coming in above 40. So, the big thing about Paris is we need to have the means to accelerate cuts thereafter."
The Chinese character for "crisis" is composed of two characters, one representing danger and the other, opportunity. No where is this more significant than in our current challenge with climate change.
Standing at this fork in the road, it is important to understand that we have a choice. We can either continue down a business as usual pathway, or embrace a low carbon future which our children and grandchildren deserve. Wrapping up a tightly packed lecture, Stern concludes:
"I'm profoundly optimistic about what we 'can' do. I don't know what we 'will' do. But, if we can do it, then we will be able to rise to the two defining challenges of this century: overcoming poverty and managing climate change. And, we if we fail with one, then we will certainly fail with the other."