Harvard-Nanjing study releases 'bottom up' estimates of China's CO2 emissions

Washington -  Atmospheric scientists at the Harvard School of Engineering and Applied Sciences (SEAS) along with Nanjing University have produced the first "bottom-up"  estimates of China's carbon dioxide (CO2) emissions, for 2005 to 2009, and the first statistically rigorous estimates of the uncertainties surrounding China's CO2 emissions.

"China's emissions of CO2 are of central concern in efforts to combat global climate change," lead author Yu Zhao, a former postdoctoral researcher at Harvard SEAS, who is now a professor  at the Nanjing University School of Environment in China, said.

"But despite all of the attention to China's CO2 emissions, they're less well quantified than most people realize," he added.

The Harvard-Nanjing study constructs a "bottom-up" emission inventory that is specific to China's energy and technology mix and combines the results of Chinese field studies of CO2  emissions from diverse combustion processes with a plant-by-plant data set for power generation, independent research on transportation and rural biomass use, and provincial-level  energy statistics for the remaining sectors.

The existing estimates for CO2 emissions are calculated "top-down," based on annual energy statistics that are released by the Chinese government.

The nation has only once officially estimated its CO2 emissions, based on national energy statistics from 1994, although it is now constructing a data system to produce periodic national

greenhouse gas inventories.