An ARkStorm (for Atmospheric River 1000 Storm) is a hypothetical but scientifically realistic "superstorm" scenario developed and published by the United States Geological Survey, Multi Hazards Demonstration Project (MHDP). It describes an extreme storm that may impact much of California causing up to $725 billion in damages and repair (most caused by flooding), and affect a quarter of California's homes. The event would be similar to intense California storms which occurred in 1861 and 1862.[1] The name "ARkStorm" means "Atmospheric River (AR) 1000 (k)." The name was created as a way of quantifying the magnitude of west coast storms. It also meant to be drawn as a parallel to the biblical Noah's Ark story.

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