Hard to believe 6 weeks of continuous rain, but that is what California scientists and first responders have to contend with in scenarios of possible catastrophes they face. Starting at the equator, roaming over the Pacific, affected by changes in El Nino and the global climate, an atmospheric river of moisture slams into the west coast with winds up to 125 miles per hour. Massive flooding, landslides, pollution, road damage, business interruption, housing destruction and social dislocation making Katrina look like a summer drizzle. Almost a trillion dollars of damage is estimated for a deluge that could turn Central Valley into a lake 300 miles long and 20 miles wide.

Think it can't happen? In 1862 in California a series of storms turned the Central Valley into a huge inland sea. Equivalent to possibly 50 Mississippi rivers, an atmospheric water flow lasting 45 days inundated the Central Valley, destroying the economy and forcing California into bankruptcy. Flooding was extensive in LA County, Orange County, San Diego, the San Francisco Bay area and other coastal areas. Future repetitions are expected, and 10 feet (feet-not inches) of rain over a period of roughly 40 days is what emergency authorities are discovering they have to prepare for.

The ARkStorm (Atmospheric River 1000) is actually a computer model of a storm event that has impacted the western part of California numerous times in the last 2000 years and as recently as the aforementioned 1862. It is the brainchild of the US Geological survey, Multi Hazards Demonstration Project (MHDP). The first public product of this survey was the Shakeout Earthquake Scenario published in May 2008. It resulted in the largest earthquake drill in US history, and depicted a 7.8 magnitude earthquake on the San Andreas Fault in southern California. Over five and a half million citizens and 5000 emergency responders got a chance to explore the consequences of such a devastating catastrophe. The intent of the ARkStorm project is to provide realistic information to the proper authorities to help them prepare for an even greater calamitous natural disaster.

Serious issues are raised about the ability of local and state disaster planning to handle a disaster of this magnitude. Whether to pay in advance to mitigate the effects of such a disaster or to pay a lot more to rehabilitate a ruined landscape and the dislocation of 1.5 million people after the fact are decisions which need to be faced. In the current time of fiscal distress, this is likely to be a problem shoved under the carpet for someone else to worry about. But hoping ARkstorm remains a hypothetical study and nothing more is irresponsible. The scientists have done their job. Now it is up to government-good luck!