Now in its 43rd year, Earth Day has become an international day dedicated to promoting environmental awareness and action. Lester Brown, president of the Earth Policy Institute, explains what's changed, as concern about climate change and green energy have come to the forefront of the movement.
43 Years Of Earth Day: What's Changed Since 1970
By editor • Apr 22, 2013
Originally published on April 22, 2013 1:51 pm