Urban Ecoist

Maybe all remember the 2008 Summer Olympics in Beijing (or maybe not, Michael Phelps…), and if you do remember than perhaps you also recall that the city of Beijing went to some lengths to curb its air pollution during the course of the Games.

Well, the data is being analyzed by some researchers that want to see what kind of tangible reductions in particulate pollution came with that olympic effort to cut back on industrial and automobile emissions.

Atmospheric scientist Jan Cermak of the Swiss Federal Institute of Technology Zurich and a a mysteriously unnamed colleague looked at the aerosols in the atmosphere above the city of Beijing from the years 2002 through 2008. They used satellite data, which could measure the aerosol levels, but not the true location in terms of high-atmosphere or lower ground levels. Wind patterns, weather reports, rainfall, humidity — these factors were all taken into account to determine what the aerosol levels would have been during the Olympics and what they actually were from July to September 2008.

And guess what? It really didn’t matter what Beijing did. The city achieved some reductions in aerosol levels, but really nothing to get excited about. And why, you ask? Because so much air-bourne pollution came in to Beijing’s skies from other regional sources.

It turns out that the Chinese only achieved a modest reduction in aerosols. The researchers report in a paper in press in Geophysical Research Letters that pollution-control efforts reduced the overall amount of aerosols in the atmosphere by about 10% to 15%. That small change highlights the importance of factors such as wind direction in determining local pollution, says Cermak. In spite of the reduction in local emissions, winds from the south and southeast sullied Beijing’s air by bringing in pollution from distant industrial areas, he says. — Science Magazine News

You see, that’s the funny thing about air-bourne pollution. It doesn’t stay still like land-based pollution. Oh, wait, land-based pollution doesn’t stay put, either. It leaches into the water supply. Huh, maybe we should just try harder not to pollute in the first place.

Naw, that will never work.

Still, the numbers show that Beijing did achieve a 10 to 15 percent reduction in aerosols above the city. Am I the only one who thinks that is a good start? Too bad the Chinese only did it for three months. Who knows what reductions could be achieved with a long-term cut in emissions?

air pollution, Olympics, China, Beijing, emissions, aerosols, atmosphere