Time is running out to avert ‘dangerous’ climate change, says the IEA. But are deadlines and temperature targets too arbitrary?

We may be in for a world of hurt before this decade is out. The clock is now ticking on two nearly back-to-back deadlines that we are almost certain not to meet.

In 2006, NASA climate scientist James Hansen warned:

“I think we have a very brief window of opportunity to deal with climate change … no longer than a decade, at the most.”

That window is closing fast, and most climate observers say that significant action by 2016 is a reach. But wait: An extension of sorts has just been announced. Fatih Birol, chief economist at the International Energy Agency (IEA), now has tacked on a year, telling the Guardian:

“If we do not have an international agreement, whose effect is put in place by 2017, then the door to [holding temperatures to 2C of warming] will be closed forever.”


The 2C threshold has become a benchmark in climate policy. Staying below it means not exceeding 450 parts per million (ppm) of carbon dioxide in the atmosphere. But that seems increasingly doubtful as the world currently is at about 390 ppm and on a locked-in oil- and gas-dependent trajectory, according to a new report issued by the IEA. In its summary of the findings, the Guardian wrote:

The world is likely to build so many fossil-fuelled power stations, energy-guzzling factories and inefficient buildings in the next five years that it will become impossible to hold global warming to safe levels, and the last chance of combating dangerous climate change will be “lost for ever”, according to the most thorough analysis yet of world energy infrastructure.

But like the deadlines issued by Hansen and Birol, is the 2C threshold also an arbitrary target? Richard Betts, the head of Climate Impacts at the UK’s Met Office, thinks so. In a recent online discussion forum he asserted:

Most climate scientists do not subscribe to the 2 degrees “Dangerous Climate Change” meme (I know I don’t). “Dangerous” is a value judgment, and the relationship between any particular level of global mean temperature rise and impacts on society are fraught with uncertainties, including the nature of regional climate responses and the vulnerability/resilience of society.

Betts agrees that “climate change is a serious issue and it makes sense to try to avoid committing the planet to long-term changes.” But he’s concerned that the 2C benchmark sets up climate policymakers for certain failure. He says:

The thing that worries me about the talking-up of doom at 2 degrees is that this could lead to some very bad and expensive decisions in terms of adaptation. It probably is correct that we have about 5 years to achieve a peak and decline of global emissions that give a reasonable probability of staying below 2 degrees, but what happens in 10 years’ time when emissions are still rising and we are probably on course for 2 degrees?

One likely answer: The deadline gets pushed back another few years. By then, all the dire warnings either will have caused people to tune out or, if projected climate impacts worsen, to finally pay attention.

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