Air pollution impacts health and even contributes to millions of deaths each year. Until now, measuring pollution across the globe has been difficult. Land sensors are few and far between and only give a snapshot of pollution levels for a small area. In recent years, new satellites circling the Earth have instruments on board that can now measure pollution on a global scale. That satellite data is fed into computer models to give scientists a more accurate idea of how pollution is distributed through the Earth's atmosphere.
The below map shows how the distribution of air pollution related to human activity between 2000-01 and 2008-09 chance across the Earth. This is a computer simulation based on the satellite data. The simulation focuses on pollution from humans burning fossil fuels and forests. Natural particles in the air, such as blowing dust, volcanic ash, and sea salt, were not included.
According to NASA Earth Observatory, orange shows where pollution increased while blue indicates where levels decreased. Note the significant decrease over much of Europe and eastern North America. However levels increased dramatically over parts of Asia.
"Asian countries, particularly China and India, have been releasing more particulate matter into the air as they urbanize, while European countries and the United States of America have seen pollution levels decline as more efficient, cleaner-burning technologies have become more widespread." says NASA Earth Observatory.
The increase in Africa is not related to fossil fuel burning, but instead from farmers clearing the land for agriculture by burning the acreage.
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