Is 6% the World's Most Important Number?

6% THE WORLD'S MOST IMPORTANT According to audit and consulting firm PwC, for the world to continue growing economically at current rates without exceeding 2 C warming of average surface temperature over preindustrial levels, carbon intensity – the amount of carbon released per unit GDP –- needs to be reduced by 6 percent annually from now to 2100. The problem? That's nine times the current rate of decarbonization. 2034 Given current rates of carbon intensity, we'll use up this century's entire carbon budget – the amount of carbon that can be released while still retaining a reasonable probability of limiting warming to 2C - by 2034. ZUJ4 Ninety-two percent of the reduction in carbon intensity in 2012 was due to energy efficiency fruit," according to PwC. 92% the "low-hanging STEPS FORWARD The following activities, if scaled up (or down) drastically, could move us closer to the 6 percent target. Some – such as nuclear energy and biofuels – are surrounded by considerable debate. CO2 IMPROVE INCREASE COMMERCIALIZE REDUCE EMISSIONS FROM RECONSIDER ADVANCE DECREASE ADVANCE EFFICIENCY RENEWABLE CARBON CAPTURE NUCLEAR LOW-CARBON DEFORESTATION CIRCULAR ENERGY & SEQUESTRATION ENERGY BIOFUELS AGRICULTURE ECONOMY THE BIG SOLUTION One solution rises above all others in the PwC report: A global climate deal that could "provide the regulatory framework and financial stimulus to catalyze a low carbon transition." A climate agreement that includes carbon pricing would be the biggest step forward. SOURCES: Pacala, S., and Socolow, R. 2004. Stabilization wedges: Solving the climate problem for the next 50 years with current technologies. Science 305:969-72; Romm, Joseph. 2008. Cleaning up on carbon. Nature Reports Climate Change 7:85-87. doi:10.1038/climate.2008.59; PwC. 2013. Busting the Carbon Budget: Low Carbon Economy Index 2013. pwc.co.uk/en_UK/uk/assets/pdf/low-carbon-economy-index-2013.pdf. The Ellen MacArthur Foundation. Circular Economy, ellenmacarthurfoundation.org/circular-economy; Winston, A. 2014. The Big Pivot. Boston: Harvard Business Review Press; International Energy Agency. iea.org CREDIT: Infographic text by Todd Reubold; infographic layout and icons by Anna Egelhoff; Photo © istockphoto.com/halbergman ensia.com