Global carbon dioxide emissions soared from 22.7 billion tonnes in 1990 to 33.9 billion tonnes last year, despite 20 years of attempted mitigation (Nature 491, 656–658; 2012). The sizeable economic gaps between nations are largely responsible for the international deadlock in climate negotiations. A radically new approach is needed.

One solution would be to allocate common but differentiated responsibility for mitigating emissions to individual consumption activities, rather than to countries. Profligate consumers from both developed and emerging countries are the worst offenders for generating non-essential emissions. They should be held accountable for those emissions, irrespective of where they are generated.

Emissions produced after reallocating responsibility in this way could be quantified for nations, lifestyles or even every product consumed. This could be achieved by integrating the 'top-down' consumption-based accounting methods that are used to determine national total consumption emissions with 'bottom-up' carbon-footprint calculations based on analysis of products' life cycles (G. P. Peters Curr. Opin. Environ. Sustain. 2, 245–250; 2010). A living standard, together with a per capita emission quota, would be defined so that people worldwide could meet their basic living requirements without mitigation costs.

Such standardized measures would allow new cap-and-trade policies and carbon-taxing mechanisms to run smoothly and effectively across different consumption groups at a global scale (see M. Grubb Nature 491, 666–667; 2012).