New measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASAâ€™s Terra satellite detail the pollution generated from East Asian forest fires, industrial production and transportation exhaust. The rapid industrial growth of China, coupled by urban expansion, has made the country the world’s largest emitter of pollution that finds its way across the Pacific Ocean on the jetstream.
â€œWe used the latest satellite capabilities to distinguish industrial pollution and smoke from dust transported to the western regions of North America from East Asia. Looking at four years of data from 2002 to 2005 we estimated the amount of pollution arriving in North America to be equivalent to about 15 percent of local emissions of the U.S. and Canada,â€ Yu said. â€œThis is a significant percentage at a time when the U.S. is trying to decrease pollution emissions to boost overall air quality. This means that any reduction in our emissions may be offset by the pollution aerosols coming from East Asia and other regions.â€
The satellite instrument provides accurate daily measurements across a broad geographic region and a long time frame to greatly improve previous models and measurements. While this new instrument is a vast improvement, it doesn’t measure the elevation of the pollutants in the atmosphere. Without the elevation measurement, it isn’t possible to determine the impact on air quality.
“In the last two decades, China has more than doubled its pollution production. This boom may be contributing to substantial changes in climate and weather in places far from the origin of the particulates. Never in human historyâ€”anywhereâ€”has there been industrial growth like that in modern China. But with fast growth comes unintended consequences, and from space evidence of those consequences is starting to emerge.”
Researchers found that pollution movements fluctuates during the year, with the greatest impact in Spring. And Asia isn’t the only contributor, with European pollution also having an impact on North America. It can take as little as one week for pollutants to make their way across the pacific.
You can learn more about this research, and view an animation of pollution, on the NASA website.