How Sure Are Scientists About Global Warming?

How Sure Are Scientists About Global Warming?
Commonwealth Club - The Commonwealth Club of California
It has taken just three centuries for human growth and rising industrial economies to bring the delicate relationship between ice and humans to a dangerous precipice. Ice carved Earth's landscape to its present state - the sharp Alpine peaks of Europe, the vast Great Lakes of North America, the majestic valleys of Yosemite National Park and the deeply incised fjords of Norway.But as the climate change debate becomes more heated, are we at risk of losing these precious formations? Dr. Henry N. Pollack, author of A World Without Ice, explains why our cold natural wonders are disappearing while humans are prospering.