1/3 of Lead Air Pollution Found in San Francisco Originated in Asia
Regulating pollution is a notoriously difficult enterprise, and that's largely because particulates or emissions spewed in one place may end up impacting folks thousands of miles away. In a new study, scientists have gone a long way in underscoring the truly transient nature of pollution. They've found that about "a third of the airborne lead particles recently collected at two sites in the San Francisco Bay Area came from Asia."According to PhysOrg, the study, conducted by scientists from the U.S. DOE's Lawrence Berkeley National Laboratory and the California Air Resources Board, is considered the first of it's kind. It's primary goal was to track "variations in the amount of lead transported across the Pacific over time."
They used the lead particles' isotopic signature as a chemical return address, which enabled them to trace some of the lead's origins to coal and metal ore found only in Asia ... It's well known that particles and other aerosols cover long distances through the Earth's atmosphere. But the details of this transport, such as that of the lead particles' 7,000-mile journey from the smokestacks of China to the west coast of North America, are largely unknown. That could change.This study drives home the unfortunate truth about air pollution: It's everyone's problem. If smokestacks on a Chinese factory are belching pollution, nations around the world will feel the impacts. Same goes, say, for coal plants in the United States -- and any other emissions-intensive industrial operation, for that matter.
"This work shows that we can use lead as a tracer for airborne particles within the growing Asian industrial plume," adds Christensen. "We can use lead to more thoroughly understand the conditions over the Pacific Ocean that promote the transport of aerosols from Asia to the U.S."
This has, of course, long been the sticking point in trying to address greenhouse gas emissions on a global scale -- the atmosphere doesn't care which nations are causing CO2 to concentrate, and climate change impacts countries whether they contributed emissions or not.
In an ideal world, these findings about airborne particulate pollution will lead to more rigorous international pollution limits -- or at least a means to pressure nations with rampant emissions to clean up their act.