They point out that LA is a huge bowl shape with few ways in and out for the # of people, dble decker highways etc

Doom: Take yer pick

Asteroid in the Ocean causing a tsunami

Supervolcano (long valley)

Big earthquake



All would basically cut people off, once the highways go they're out of luck

Event big enough most would perish

Any survivors would have to walk out, wouldn't have food or water

They tell people to garden in their limited spaces, indoors too - microgreens, have a year's worth of food on hand, plan several escape routes

me: when they said bowl shape I immediately thought of New Orleans