The Other Big One

The Other Big One

One of the big stories of late 2010 and early 2011 is the weather. We're sharing this Jan. 19 post from Jim Loveland's blog.

One of the big stories of late 2010 and early 2011 is the weather. In the United States severe snow storms led to damage from New England to Georgia and rain caused mudslides and flooding in California. Wet weather in Brazil recently brought mudslides that led to a horrific loss of life. Much of Europe has experienced the coldest winter in many years. Australia has seen unprecedented flooding that has insurers scrambling to keep up with the volume of claims.

Of course weather-related damages are occurring constantly but the scale of the Australian floods in particular has many taking a closer look at important catastrophe information such as the excellent models created by our sister companies AIR Worldwide and AER.

Last week the USGS released a report that contained a sobering winter-storm scenario for California. Based in part on the winter storms that struck California in 1861-62, the report calls the scenario the “other Big One” because damages could be three times as much as a southern California earthquake. Compiled by the USGS’s Multi Hazards Demonstration Project (MHDP), the report says insured damages could be in the range of $20 to $30 billion with total damages at around $300 billion. Much of the projected insured damage would be covered by the National Flood Insurance Program and the report uses NFIP data for some of its property and property contents loss projections.

The 1861-62 series of extreme winter storms started in December of 1861 and did not end until 45 days later in early 1862. The storms brought hurricane-strength winds, heavy rain, and huge surfs. Reporting in January of 1862, William Brewer wrote, “The great central valley of the state is under water—the Sacramento and San Joaquin valleys—a region 250 to 300 miles long and an average of at least twenty miles wide, or probably three to three and a half millions of acres!” Sacramento remained under water for three months. California governor Leland Stanford took a rowboat to his inauguration.

The report found geologic evidence of six similar megastorms that struck the region before the arrival of Europeans. Those storms were even bigger than the 1861-62 storms.

For more information about weather and catastrophe modeling check out the websites of AIR Worldwide and AER.