Witness the awesome power-and the unimaginable destruction-of explosive volcanoes, ground-buckling earthquakes, and deadly tornadoes as you head into the field with scientists who risk their lives exploring the origins and behaviors of these fearsome natural disasters. It's a spectacular, up close glimpse of the Earth's most destructive forces! Narrated by Kevin Bacon.

Hurricane Katrina may well be the most exhaustively chronicled natural disaster in history. Over the course of 72 hours, a cataclysmic storm became a catastrophic flood, which in turn became an apocalyptic human tragedy. All the while, amateur videographers, news crews, government agencies, tourists, storm chasers, and countless others were recording the sights and sounds of the unfolding chaos. Weaving together more than a hundred of these sources, Witness: Katrina reconstructs Hurricane Katrina as it happened, entirely through the eyes of those who experienced it. From Biloxi to Bay St. Louis, from Slidell to the Superdome, this 90-minute special captures the storm and its aftermath in all its epic human complexity - raw images of fear, grief, and anger, side by side with unforgettable moments of humor, grace, and joy. Timed to coincide with the fifth anniversary of the storm, Witness: Katrina is both a riveting documentary and an enduring document - the portrait of a defining moment in American history.

The "super outbreak" of April 26-27 alone involved more than a hundred separate twisters, killing over 300 people and cutting a path of destruction across the south. Witness: Tornado Swarm 2011 tells the story of this once in a century event, captured by those who lived to tell about it.

An American photographer is buried alive during the Haiti earthquake. With the help of news footage and photos he took from inside the crumbled building, he shares his harrowing story of being trapped inside. A family in Iowa records a deadly tornado barreling down on their home, and haunting images of the devastation and destruction that followed. A skier tells his chilling account of surviving an avalanche and storm chasers put their lives on the line while documenting a Florida Hurricane with 150mph winds.