Growing up, I'd look outside on days like this and think about fog and low-lying clouds and decreased visibility. Now, in China, I look out into the haze and reflexively check for the pollution levels. PM2.5, PM10, SO2, NO2, carbon monoxide, ozone. The numbers are recorded at multiple stations in every city, and tracked by nearly every smartphone. They spur the sale of masks and air purifiers as people seek to create their own little bubbles of safety. They keep children indoors and send expats from the country. On particularly bad days, those who boldly venture out unmasked come home with burning eyes and sore throats. And yet may locals eschew the masks because, well, they've become accustomed to this. It's the new normal.
PM2.5 (pronounced "PM èr diǎn wǔ" in Mandarin), the most worrying pollution figure, refers to fine particles in the air which are less than 2.5 microns in diameter. It's is a daily topic of conversation here. These particles are readily inhalable and are small enough to lodge in your alveoli, the small subunits of your lungs where oxygen and carbon dioxide are exchanged with each breath. From there, any soluble pollutants can pass into your bloodstream; insoluble particles remain in the alveoli, causing inflammation. Exposure to high levels of PM2.5 has been linked to a number of health conditions, including the rapid rise in lung cancer cases in Beijing (the staggering number of smokers also plays a role there).
Lest I scare off potential visitors, I should say that life in Shanghai is usually quite comfortable, and the air is usually quite breathable. In my nearly-one-year experience, these pollution levels are uncharacteristic for us. (I make no such claims about Beijing. Generally, pollution in northern China is significantly worse than southern China.) For any big polluters, though, the ones back in America pumping crap into the air and the water and the soil because they don't believe it'll make a difference in their lifetime, I invite them to spend some time in Northern China. See what it's like to live in a place where you worry with every breath, where water free of bacteria and heavy metals comes only in bottles, where there's no way to know whether your perfectly normal-looking fruits and vegetables were grown in contaminated soil. That's what's coming here if they don't turn things around. It could happen there too.
Summer in Beijing
Where does the pollution come from? Why are China's problems so much worse than anywhere else? (with some exceptions. New Dehli, for example, is sometimes worse than Beijing.) While I don't claim to be an expert, rapid industrialization is largely to blame. Pollution levels climb as a result of combustion in power plants, cars, and, if you pay attention to the Chinese government crack-downs, barbeques. According to stats from Greenpeace, 70% of China's power comes from coal; in 2009, it burned as much coal as the rest of the world combined. On the roads, China's emission standards for gasoline are significantly lower than America's, which means the millions of cars in its mega-cities (23 million people in Shanghai alone) drive dirtier. There's market pressure from the SOEs (state-owned enterprises) involved in trucking and transport to keep gasoline standards low. Geography also plays a role in some areas, including Beijing. Beijing sits in a bowl, surrounded by mountains on three sides, and is susceptible to sandstorms from the Gobi Desert.
Some argue that every industrialized nation had the chance to grow fast and dirty before cleaning up its act (see: peppered moth evolution in Industrial Revolution England), and that this is China's turn.
At what cost?
I think the next decade could bring big changes in China's environmental policies. The people are demanding it.