Immense energy emissions challenge “not understood”

Carnegie Insititution of Washington’s Steven Davis

Sometimes, climate change seems unstoppable – so much so, it’s tempting to ask: ‘Why bother doing anything about it then?’ Steven Davis of the Carnegie Institution of Washington and his colleagues have provided one answer. They have found that while the power generation facilities and transportation we currently use guarantee some CO2 emissions, those emissions will not themselves reach levels that could cause dangerous climate change.

“The result is hopeful in that what we’ve already built won’t put us over the 2ºC benchmark,” Davis said. A 2°C temperature rise from pre-industrial averages is a stated aim of the Copenhagen Accord, agreed by the world’s countries in December last year. However, Davis warns that taking the right steps to stop emitters yet to be built taking global temperature rises through this limit is a difficult, in fact almost impossible, challenge. “The necessary transition in our energy system is incredibly daunting,” he explains. “The immensity of the challenge is not commonly understood, the political will is lacking, and there are few alternative energy technologies that can attain the required scale.”

But despite the size of the challenge, even showing how much effort is needed to reduce emissions is important. “It establishes a minimum for future emissions if existing devices live out normal lifetimes,” Davis explains. That’s important because understanding of the world’s in-built resistance to any efforts to change ongoing trends – often called inertia – has been lacking.

“The inertia of climate change has long been a point of interest both for scientists and policy makers who want to understand what impacts are unavoidable,” Davis explains. “Until now, research has focused on how much warming will occur if the greenhouse gas concentrations in the atmosphere remain constant at today’s levels. We’re trying to get at a different kind of inertia – that of the energy system we have in place today.”

Davis admits that he was surprised that the results of the modelling that he and his colleagues performed suggest that energy system inertia isn’t already enough to pass the 2ºC mark. And while he is pessimistic about humanity’s ability to stay within this limit, he admits how energy systems change from here is up to us. “With a price on carbon and large infusions of public dollars for research and development, we could see more electricity generated by nuclear, solar and fossil fuels paired with carbon capture and storage,” he says.

Figuring out how those changes should be made, and where emissions should be cut, is a thorny issue, however. Different countries are responsible for very different proportions of the emissions that current technology commits us to. China alone accounts for roughly 37 percent, while Europe and the US each account for around 15 percent, and India accounts for 5 percent.

The projected decline of CO2 emissions from power generation and transport in use today in gigatons (billions of tons) from existing energy and transportation infrastructure (multicolored wedge) over the next 50 years. Colors within the wedge indicate projected emissions by various countries and regions. Credit: Stephen J. Davis

“The different types and ages of infrastructure that exist today do lead to quite different estimates of future emissions from different countries,” Davis says. However he emphasises that his research is not meant to answer questions of who does what. “The scenarios we’ve developed aren’t meant to be a prescription for what emissions from different countries should be to meet climate targets.”

Finding the determination to change how we produce and use power can be hard, because it’s a process that’s largely invisible to us. However, bearing in mind that power generated from burning fossil fuels produces CO2, Davis has a simple explanation of the reasons why we should.

“I like the metaphor of a car parked in the sun,” Davis says. “The earth is the car, and the car’s windows are CO2. Humans evolved on a planet with relatively low CO2 – the windows a good way down and a nice breeze blowing through. But every molecule of CO2 we put in the atmosphere inches the windows up, and the car is heating up uncomfortably.”

There are several obvious choices of how to act in this situation, Davis notes. “We can stop rolling up the windows – stop emitting CO2,” he says. “We can try to find ways to survive in the hot car – which is known as adaptation when related to climate change. We can put up some sort of shade to keep the sun out, which would be geoengineering, or we can pretend it’s not hot, which is denial.”