Japan, home of the Kyoto Treaty, is being overwhelmed by smog. Experts blame China.
Warnings for high levels of smog have been issued for a record 28 Japanese regions.
The type of smog – known as “photochemical smog” because it forms when sunlight reacts with exhaust – is a special concern because it can cause breathing difficulties and headaches. Smog can also cause acid rain and sandstorms.
"In terms of average levels of photochemical oxidants measured annually across Japan, there has been quite a rise since the 1990s," Toshimasa Ohara, head of the National Institute of Environmental Studies' regional atmospheric modeling section, told Reuters. "We believe a substantial part of that rise has come from increasing emissions in China. We're looking into what percentage this factor has accounted for."
As a first step, government officials say Japan is working with China to measure pollution.