John Wesley Powell Memorial Lecture

On today's show, we speak with Dr. Laurence Smith, a professor of geography at UCLA, about his much-discussed book, "The World in 2050: Four Forces Shaping Civilization's Northern Future," which first appeared in 2010 (and which The Wall Street Journal called "lively and impressive...[and] among the first in what promises to be an important publishing category, the explication of how the human landscape will be altered by artificially triggered climate change"). Dr.