"All the problems we face can be dealt with using existing technologies. And almost everything we need to do to move the world economy back onto an environmentally sustainable path has already been done in one or more countries." –Lester R. Brown, Plan B 3.0: Mobilizing to Save Civilization
Now in its 43rd year, Earth Day has become an international day dedicated to promoting environmental awareness and action. Lester Brown explains what's changed, as concern about climate change and green energy have come to the forefront of the movement.