Bookmark and ShareDr Victoria Johnson is a researcher on the climate and energy team at nef.

In one version of the story of the biblical flood, Noah gets the chance to pass on God’s warning of the coming deluge. One hundred and twenty years before the rain starts falling, Noah plants cedar trees so that he can have wood to build the ark and so that the ‘sinful’ can see what’s going on and amend their ways.

Step forward a few thousands of years and the story is being played out along much the same lines: climate scientists began planting their cedar trees at least two centuries ago, through research and the development of climate models.

Joseph Fourier proposed the existence of a ‘greenhouse effect’ way back in 1824. And at the Mauna Loa Observatory in Hawaii, scientists have been measuring CO2 levels in the atmosphere since 1958. When Charles Keeling first set up Mauna Loa, the atmospheric concentration of CO2 was between 312 and 313 parts per million by volume (ppmv). It has now climbed beyond safe levels to 385 ppmv (end of 2008), 42 per cent above the concentration at the start of the industrial revolution, and rising at a rate of approximately 2.2 ppmv per year.

Despite the exponential growth in research into climate change since the 1950s, we’re still heading in the wrong direction. As Andrew Weaver of the University of Victoria put it in the latest edition of Nature,  ‘climate scientists have begun to feel like a bunch of Noahs – thousands of Noahs’.

In the same issue, two climate papers have again shown that we are fast approaching dangerous levels of greenhouse gas concentrations that threaten to take us beyond a global surface temperature rise of 2 ºC relative to the pre-industrial era. And yet, there is nothing particularly ‘safe’ about global surface temperature rise of  2 ºC. As Professor Rahmstorf from the Potsdam Institute says: If we look at all of the impacts, we’ll probably decide that two degrees is a compromise number, but it’s probably the best we can hope for”. Indeed, NASA’s James Hansen argued in 2007 that temperatures should not go beyond 1.7 ºC if we are to avoid aiming to avoid practically irreversible ice sheet and species loss.

Malte Meinshausen, the lead author of one of the papers, found that in order to stand a 75 per cent chance of keeping temperatures below 2 ºC the world has to limit the cumulative emissions of all greenhouse gases to approximately 1.5 trillion tonnes of CO2 equivalent. To reduce the risk by another 5 per cent, this means capping total emissions to just over 1 trillion tonnes of CO2 equivalent. Myles Allen comes to similar conclusions – if humans can limit cumulative emissions of carbon to 1 trillion tonnes of carbon, there is a good chance not exceeding the 2 ºC. They estimate that we could follow our current emissions pathway for another forty years, and then would have stop emitting carbon altogether. But, this doesn’t mean we’ve got forty years, far from it. Meinshausen argues that if emissions are still 25 per cent above 2000 levels in 2020, the risk of exceeding 2 ºC shifts to more likely than not.

That’s a reduction in global emissions by 2.5 per cent year on year starting now.  But can we do it?  Jonathan Schell in his book The Unconquerable World: Power, Nonviolence, and the Will of the People argues that revolutionary change must first take place in the imagination. In other words, the seeds of change are sown through imagining what is possible, and a belief that change is possible.

But first, the tough facts, the latest figures from the Global Carbon Project, an international collaboration between leading climate research institutions, has estimated that the average annual growth rate in emissions has been 3.5 per cent between 2000 and 2007. At the same time, globally, there is no sign of a slowing in the growth of emissions; there has been a constant or slightly increasing trend in the carbon intensity of energy (carbon emissions per unit of energy) over recent years, in both developed and developing nations.

Of the 3.5 per cent average annual growth rate of emissions between 2000 and 2007, 18 ± 15 per cent of the growth rate is due to carbon-cycle feedbacks, while 17 ± 6 per cent is due to the increasing carbon intensity of the global economy (ratio of carbon per unit of economic activity). The remaining 65 ± 16 per cent is due to the increase in the global economic activity.

While it is oft-argued that technological innovation could in theory improve resource and energy efficiency and lead to decarbonisation of the economy, recent evidence challenges this view. Current estimates to the future evolution of energy and carbon intensities used by the IPCC emission scenarios, which assume that up to two—thirds of the energy efficiency improvements will occur spontaneously are: ‘arguably unrealistic and some are likely to be unachievable’. Indeed, the IPCC assumptions for decarbonisation of the economy in the short term (2000-2010) are already inconsistent with recent evolution of the global economy. Instead of declining energy intensity of the economy and carbon intensity of energy both have risen in recent years, reversing the trend in previous decades.

“we wouldn’t fly in a plane that had more than a 1 per cent chance of crashing. We should be at least as careful with the planet.”

“We wouldn’t fly in a plane that had more than a 1 per cent chance of crashing. We should be at least as careful with the planet.”

The monstrous overplaying of the feasibility of carbon capture and storage and the frankly feeble “green” economic stimulus packages makes it seem as if there is concerted effort to chop down the scientists’ cedar trees as quickly as they can plant them.

Surely this says it all – it’s time for a rapid transition. And perhaps, with the rise and rise of the climate activist movement, things might start to shift. Despite the mess we’re currently in, I still hold onto the hope that, in 91 months time, the old carbon intensive regime will have vanished and we’ll be well on our way to the low carbon, high well-being economy that we know is possible. As Schell writes:

“Individual hearts and minds change; those who have been changed become aware of one another; still others are emboldened to, in a contagion of boldness; the ‘impossible’ becomes possible; immediately it is done, surprising the actors almost as much as their opponents; and suddenly, almost with the swiftness of thought – whose transformation has in fact set the whole process in motion – the old regime, a moment ago so impressive vanishes like a mirage.”

As Paul Sutton of the Carbon Equity project put it, “we wouldn’t fly in a plane that had more than a 1 per cent chance of crashing. We should be at least as careful with the planet.”