Iain Stewart investigates a new and controversial energy rush for the natural gas found deep underground. Sometimes, this is right under the places people live in. Getting it out of the ground involves hydraulic fracturing - or fracking. Iain travels to America to find to find out what it is, why it is a potential game changer and what we can learn from the US experience. He meets some of the people who have become rich from fracking as well as the communities worried about the risks.
Rip currents can appear without warning, turning an ideal beach outing into a horrific scene of chaos and panic. But groundbreaking new research could teach thousands of potential victims how to spot and escape these silent killers before it's too late.
All over the world, scientists are discovering traces of ancient floods on a scale that dwarfs even the most severe flood disasters of recent times. What triggered these cataclysmic floods, and could they strike again? In the Channeled Scablands of Washington State, the level prairie gives way to bizarre, gargantuan rock formations: house-sized boulders seemingly dropped from the sky, a cliff carved by a waterfall twice the height of Niagara, and potholes large enough to swallow cars. Like forensic detectives at a crime scene, geologists study these strange features and reconstruct catastrophic Ice Age floods more powerful than all the world’s top ten rivers combined. NOVA follows their efforts to uncover the geologic fingerprints of other colossal megafloods in Iceland and, improbably, on the seabed of the English Channel. There, another deluge smashed through a land bridge connecting Britain and France hundreds of thousands of years ago and turned Britain into an island for the first time. These great disasters ripped through terrain and transformed continents in a matter of hours—and similar forces reawakened by climate change are posing an active threat to mountain communities throughout the world today.
Professor Iain Stewart uncovers clues hidden within the New York skyline, the anatomy of American alligators and inside Bolivian silver mines, to reconstruct how North and South America were created. We call these two continents the New World, and in a geological sense they are indeed new worlds, torn from the heart of an ancient supercontinent - the Old World of Pangaea.