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NOVA: Killer Floods

Airs Wednesday, April 22, 2020 at 10 p.m. & Sunday, April 26 at 2 p.m. on KPBS TV + Thursday, April 23 at Noon & Sunday, April 26 at 9 p.m. on KPBS 2 + PBS Video App

Dettifoss Waterfalls, Iceland.

Credit: Courtesy of Blink Films

Above: Dettifoss Waterfalls, Iceland.

Scientists Uncover Geologic Fingerprints Of Colossal Floods That Ripped Through Ancient Landscapes

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?

NOVA: Killer Floods: Preview

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.

Over a vast expanse of Washington State called the Channeled Scablands, 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 resembling ones scoured out by rivers today, but ten times bigger.

Photo credit: Courtesy of Blink Films

Scablands, Wash., USA.

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.

Photo credit: Courtesy of Blink Films

Dr. James Lawrence is a Senior Lecturer in Engineering Geology and Geotechnics at Imperial College London. In this photo he is seen abseiling the White Cliffs of Dover, UK.

NOVA follows their efforts to uncover the geologic fingerprints of other colossal megafloods in Iceland and — improbably — on the seabed of the English Channel, where hundreds of thousands of years ago, another deluge smashed through a land bridge connecting Britain and France and turned Britain into an island for the first time.

First Time Britain Left Europe

Geologists think these iconic chalk cliffs hold an extraordinary secret.

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.

Photo credit: Courtesy of Blink Films

Dettifoss Waterfalls, Iceland.

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Photo credit: Courtesy of Blink Films

Glacial Lake Missoula, Missoula, Mont., USA.

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