A collaborative, six-year study of carbon dioxide (CO2) levels in Beijing and surrounding provinces suggests that combustion efficiency, a component of overall energy efficiency, is improving in the region. The findings, published in the September 21 issue of Atmospheric Chemistry and Physics, are generally consistent with official Chinese government statistics and could bolster their credibility as international negotiations proceed on commitments of China and other nations to combat climate change.

A team of atmospheric scientists and environmental engineers from Harvard University and Tsinghua University in Beijing have continuously measured atmospheric CO2 and carbon monoxide (CO) levels in rural Miyun, about 100 km northeast of Beijing, since November 2004.

Weather observations such as wind speed and direction (with other evidence) allowed researchers to identify plumes of polluted air from the Beijing urban area and population centers to the south, as opposed to relatively clean air arriving from the north.

The measurements provide the most detailed look at carbon emissions for a specific urbanized and industrialized region of China to date. Moreover, the resulting analysis of CO2 and CO levels is generally consistent with China’s official statistics, showing an upward trend in overall energy efficiency.