Today is the 40th anniversary of the first Earth Day and the air quality in the United States today is at it's best over that time period.
A couple of weeks ago, Dr. Mark J. Perry, a professor of economics and finance at the School of Management at the Flint campus of the University of Michigan, published an article on his Carpe Diem blog about how much the air quality has improved over the last 40 years.
In his posting he mentions that the U.S. population has increased by more than 50%, traffic volume (miles driven) in the U.S. has increased 160%, and real GDP has increased 204%; and yet air quality in the U.S. is better than ever - nitrous dioxide, sulfur dioxide, carbon monoxide and lead have all decreased between 46% and 92% between 1980 and 2008.
In the posting he also published a graph showing air quality trend data from the EPA:
Please click here to read the full article.
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