Poofographic. Michael Pritchard makes filthy water drinkable. Visualizing video at the speed of light — one trillion frames per second. The Secret to Rising Sea Levels - Thermal Expansion. Geerup's Terrible Lizard Classification. Ask a Physicist 5. Geomagnetic Reversal (The End of the World?) Allan Savory: How to green the world's deserts and reverse climate change. Speak Out for Science. TEDxTC - Jonathan Foley - The Other Inconvenient Truth.