The worst smog of the year so far swept into Beijing this week, coating the city in a grainy, deep grey murk on par with what the city endured in 2013, pictured above (though you'll see it's popping up again today). China is trying, hard, to get its air quality problem under control, and is considering some seriously wacky ways to do it. Unfortunately, the only one that will work is also the most difficult.


If you're in Beijing right now, here's what you're dealing with: Extraordinary levels of a small particulate called PM2.5, which is great at hanging out in midair for long periods of time. PM2.5 comes from industrial sources and wood-burning fires, and it's as dangerous to human lungs as it is good at staying put. The World Health Organization recommends that the max amount of the stuff we can breath is 25 micrograms per cubic meter. Beijing hit 568 today.

The really startling thing, of course, is that this isn't all that uncommon. The concentration has hit 993, almost twice as bad as this week's levels, before. Smog comes, you don a mask and stay inside as much as possible, and smog goes. China is actually pretty good at controlling it when it matters—when world leaders were in town for APEC's annual summit in November, locals jokingly described the clear sky as "APEC blue." Pollution is so intense, it can be seen from space:


But temporary respites like the one APEC brought don't help actual residents all that much—which is why China has become a hotbed of smog-busting ad hoc design.

Making It Rain

The big tool in China's smog-busting arsenal is cloud seeding—Soviet Russia brought the concept to China in 1958, as QZ explained in a great story on artificial rain a few years ago. The idea is fairly simple: A plane (or rocket launcher) dumps chemicals—from potassium iodide, to liquid propane, to silver iodide—into an existing cloud, creating ice particles that get heavy and fall to Earth as "rain."

Rain "washes" the air of PM2.5 particles; the water molecules collect the toxic particulates and then bring them down to the ground. Technically, it's called "wet deposition," and according to QZ, China now makes 55 billion tons of artificial rain to aid in the process every year.


A rocket launcher used to seed clouds to induce rain is seen at a station of the Beijing Meteorological Bureau in Beijing. AP Photo/Ng Han Guan.

There are multiple problems with the program, including the fact that China's artificial rain program is sucking up massive amounts of precious water, as China plans massive infrastructure projects to bring more fresh water into the country. As American University professor James Lee put it to China Dialogue a few years ago: "There are so many countries involved in this that I think at some time, one country is going to say to the other 'hey, you're stealing our rain.'"


Hey, How About a Giant Sprinkler?

There are more localized plans for making it rain, though. Last year, a Zhejiang University professor named Yu Shaocai published a paper in the journal Environmental Chemistry Letters that explained a novel new method of cleansing the air with water. Shaocai envisions installing massive sprinklers atop skyscrapers that would kick into gear when needed, sprinkling the city with low-level precipitation that would normally require a cloud-seeding plane.


Shaocai's reasoning is actually pretty sound, as ludicrous as his renderings (below) may be. As we explained at the time, PM2.5 particles tend to collect closer to the ground at around 300 feet. A tower-mounted sprinkler would make it possible to target specific areas, making seeding more efficient and localized.


Paint That Eats Smog

Beyond installing gigantic shower heads atop Beijing's skyscrapers, other architecture-based smog busters do exist in the real world. The main one is a chemical called titanium dioxide, which as a pigment occurs in all sorts of products we use, including sunscreen. But over the past decade, titanium dioxide has made its way into all sorts of building materials, from bricks to paint.


That's because it titanium dioxide eats nitrogen oxides—volatile compounds that are key in producing air pollution. Nanotubes of titanium dioxide actually suck up NOx and covert it into relatively harmless nitric acid. A group of New York-based architects used the stuff to build a temporary "pollution-busting" pavilion in 2012.


Meanwhile, a hospital in Mexico was recently encased in a porous wall painted with the stuff—the more surface area, the more nanotubes—that theoretically cleanses the air as it reaches the building.

The One Where They Make Diamonds

Even deeper down the smog-busting rabbit hole is a project by the Dutch artist Daan Roosegaarde, who is working with Beijing's mayor to test a device that would sit in local parks and "gobble" pollution from the skies. Here's how Adam Clark Estes described the process when he proposed it:

Much in the same way that a static-charged balloon attracts hair, this pollution-devouring set-up uses copper coils buried under grass to create electrostatic fields and attract smog particles to the ground. Once pulled from the sky, the particles can be compressed and repurposed.


Sounds great, right? Well, wait until you hear how Roosegaarde plans to "repurpose" the compressed particles. Once they've been collected, he plans to industrially compress the waste into a tiny "gem" of toxic particulates—and then mount them on rings. "You are buying a cubic kilometer of clean Beijing air," he told The New York Times last year.


It's like the ouroboros of air pollution: Collecting smog and turning it back into a consumer commodity, to be sold in the economy that helped to create the smog problem in the first place.

Solutions Too Small For a Big Problem

So far we've got a plan to make diamonds out of smog, a plan to put huge fucking sprinklers on buildings, a plan to paint every building in every city with chemical nanotubes, and an existing program to create fake rain that could, eventually, spur a war over natural resources. Not great!


On the ground, real people have to build their own solutions—like Beijing artist Matt Hope, who built an electric air filter into a bike helmet, powered by energy generated in his pedal strokes. Or you could go even simpler and just tape HEPA filters to all the fans you've got. Oh, you could also barricade yourself in your house with a few of these suckers.

Which is to say that the real solution—the only one that will work for millions of actual people who have to deal with this on a daily basis—is also the least glamorous: Policy reform. China says it's happening, with new laws that outlaw smog-spewing cars and limit driving in general. In December, it announced that harsher penalties and more revisions to existing pollution legislation are coming.


So while engineers, architects, physicists, and one handy Beijing artist might have a ton of ideas for fixing the city's smog problem, there's only one fix that will actually work. Unfortunately, it's also the hardest.

Lead image: Beijing in 2013.