Climate change. Recent reductions in China's greenhouse gas emissions.

T he prevailing wisdom about China's greenhouse gas emissions is that they are increasing steadily, because of the large quantities of coal being used to fuel a fast-growing industrial economy, and most projections show China's greenhouse gas emissions continuing to grow in the coming decades (1). However, we find that China's CO 2 emissions declined by 7.3% between 1996 (the peak year) and 2000, and CH 4 emissions declined by 2.2% between 1997 (the peak year) and 2000 (see the figure). This happened partly because China undertook a radical reform of its coal and energy industries (2). In addition, China's economy suffered during the Asian economic crisis of 1997 to 1998 to an extent not yet fully understood (3), and many factories curtailed production or shut down because of economic restructuring policies, resulting in a decline in coal production and consumption. Although China is not a party to the Kyoto Protocol, these recent developments have important implications for the formulation of climate change policies. Focusing only on CO 2 emissions from fossil fuel combustion, against which we can compare other countries, we calculate that China's emissions dropped from 2950 Tg (teragrams of CO 2 , 1 Tg = 1 million tonnes) in 1996 to 2690 Tg in 2000, a reduction of 8.8%. This decrease, which China achieved while most other countries were increasing their emissions, represents about 1% of the global CO 2 emissions from fossil fuel combustion in 2000 of 25,300 Tg (1). In the period 1995 to 1999, CO 2 emissions from fossil fuel combustion in western Europe increased by 4.5%, in the United States by 6.3%, in Japan by 3.0%, and in India by 8.8% (4). When energy data for the past 5 years began to emerge from China , it became clear that a transformation was in progress that had resulted in a reduction in energy use (2). This transformation had several aspects to it: the closing of small, inefficient industrial plants; improved efficiency of energy end-use; improved coal quality ; the switching of many residential fuel users from coal to gas and electricity; technological progress in the energy-intensive sectors; and the opening up of coal and electricity markets. A slowdown in economic growth contributed to the decline in energy use (5). We have converted the changes in energy use and other activities into greenhouse gas emissions using guidelines from the Intergovernmental Panel on Climate Change …