Just as rich nations outsource their CO₂ emissions to China, rich coastal provinces in China are outsourcing emissions to the poorer provinces in the interior of that country. China's province-specific emissions targets will only further encourage this dynamic, despite the fact that the cheapest and easiest emissions reductions--the low-hanging fruit--are in those less developed interior provinces where the energy technologies in use are unsophisticated and inefficient.

Building on the influential "wedge" paper by Steve Pacala and Rob Socolow, we show that stabilizing emissions is only the first step in solving climate change. Ultimately we have to stop dumping CO₂ into the atmosphere altogether. Given the recent trend of emissions, a complete phase out of emissions over the next 50 years would demand at least 19 wedges, and many more if historical rates of technology improvement falter.

As part of the Global Carbon Project's RECCAP effort, this paper describes the key differences between studies of CO₂ emissions in trade and provide a consistent set of estimates using the same definitions, modelling framework, and data. Included are new calculations of carbon physically present in traded wood, crop and livestock products.

Prof. Davis is seeking outstanding graduate students and postdocs to work in the areas of energy systems analysis, land use-climate interactions, and the environmental impacts of global trade. Interested students and postdocs should contact Prof. Davis by email and describe their research interests.