The History Channel answers the question: After 650 million years of climate change, is global warming simply a naturally occurring phenomenon, or the result of human activity? Arctic ice is melting, sea levels are rising and glaciers are shrinking at alarming rates. And the Earth is getting unmistakably warmer. But is this vast potentially catastrophic climate change the result of human behavior? Or is it simply the Earth's natural cycle of warming and cooling periods that have occurred since the planet formed? An in-depth study of the science behind this controversial hot-button issue. Scientists explore the skies to examine the warming effects of the sun and dig deep into the Earth to study continental movement and the volatile activity at the planet's core. Experts speculate on how natural events including volcanic eruptions and massive meteor impacts have affected temperatures and weather systems over the planet's 600-million-year history.--Container.

Special features: additional scenes (ca. 10 min.) Videodisc release of a 2007 television program.

A rising awareness -- 10-million-year winter -- Super hot conditions -- Life forms flourish -- Far-reaching consequences -- A watery nightmare -- Evidence in the ice -- The little Ice Age -- More climate extremes -- Wrath of global warming -- Rapid escalation.; Additional scenes (ca. 10 min.) : The demise of the Anasazi -- Killer and creator -- Greenhouse gas statistics -- Snows of Kilimanjaro -- Survival of the Fittest.