This year climate scientists have worked out the total greenhouse gases or global carbon budget that we can emit and still have a reasonable chance of keeping within 2 degrees of warming. In our Low Carbon Economy Index we calculate the carbon intensity of the G20 and how fast each country is spending that budget. So what do we find this year? Since 2007 carbon intensity has only fallen by on average 0.7% annually and nearly all of that improvement is the result of energy efficiency, not the implementation of low carbon technology. This means that on current trends we will have spent the whole carbon budget for this century by 2034. Given expected economic growth we now need to reduce the emissions per unit of GDP by 6% every year, something never achieved globally, not even once. This is equivalent to halving our carbon intensity within the next 10 years, by then all countries would need to have a carbon intensity similar to that of France today and by the end of the century our global energy system would need to be virtually zero carbon.
So what’s needed for a low carbon transition? The US and China show that rapid de-carbonisation is possible. To achieve this globally, we’ll need much greater investment in energy efficiency, renewables, nuclear power and carbon capture and storage. We’ll have to tackle emissions from deforestation, there needs to be a meaningful price on carbon to support these efforts. Consumers will need to demand low carbon products and voters support the low carbon transition. But the central piece in the puzzle is a global climate change deal in which all countries commit to ambitious targets. Without this there’s the risk that decarbonisation efforts in one country just shifts emissions around the world. This is why the negotiations leading up to 2015 are so vital.