China’s size and the magnitude of its industrial activities do indeed cause it to generate large amounts of air pollution, but every country contributes to the “world’s pollution.”
The air travels across the Pacific Ocean from China to the West Coast of the United States in about five days. Scientists here at Scripps Institution of Oceanography, UC San Diego, and elsewhere have been able to observe the movement of that air and the pollution it carries from flights aboard research aircraft, at stations on the ground and by using satellite imagery. There is evidence that particulate pollution from Asia affects precipitation in California and hastens the melt of snow in the Sierra Nevada because the pollutants darken the snow, which then absorbs more solar energy than does clean snow.
Likewise, air pollution travels from the East Coast of the United States to Europe in less than five days. And air travels from Europe to Asia in a week. In short, every nation is in another nation’s back yard.
Thus, China’s pollution is only part of the “world’s pollution.” We must also count pollution from the United States, Europe, and other industrialized countries as part of the world’s pollution.
— Veerabhadran Ramanathan is a distinguished professor of climate and atmospheric sciences at Scripps Institution of Oceanography, UC San Diego.