Science of Catastrophes John M. Melack Bren School of Environmental Science and Management University of California, Santa Barbara

Flow in and through the Delta Comprises 70% of annual California runoff Supplies drinking water to 23 million people Supports a $27 billion agricultural industry

The California Delta’s evolution At sea level: land accreting Below sea level: subsidence

Land subsidence What’s wrong with this picture?

California Delta and Levees The odds of a catastrophe: 64% chance of a massive levee failure in the Delta within the next 50 years. Prof. Jeff Mount, UC Davis

California Delta and Levees “When agencies allow homes behind levees they are making one assumption. They are deciding that the occasional instances of human suffering are worth the economic benefit of development...most politicians are gambling on: Not on my watch” Prof. Jeff Mount, UC Davis

Expectations in New Orleans “Experts on hurricanes and on New Orleans say that no one should have been surprised by the impact of Katrina on the city. Many earlier storms had similar effects though at lesser magnitude... Just a year ago emergency planners from the area took part in an exercise focused on a fictitious Hurricane Pam whose effects on the city were quite similar to those of Katrina” Brian Hayes. American Scientist Nov-Dec 2005

Expectations in New Orleans “Flood control measures have hastened the loss of coastal wetlands that might have shielded the city from the storm...the land area of southern Louisiana is shrinking by 25 to 35 square miles per year.” Brian Hayes. American Scientist Nov-Dec 2005

Mangroves and tsunamis 26% of mangroves removed in last 20 years in countries hit by 2004 tsunami Remote sensing and on the ground surveys show that mangrove deforestation compounded effects of tsunami

Trends in catastrophes Fewer than 100 in 1975; More than 400 in 2005 Increase associated with severe weather and environmental degradation 15x more costly now than in 1950s More people effected as populations increase in vulnerable areas $1 spent on preparation could save $5 to $10 in reduced damage World Bank report 2006

The science of predicting disasters is uncertain Catastrophes are the great exceptions While basic factors that underlie earthquakes, volcanic eruptions, floods, etc. are well understood... Issues remain: –When and where –Unforeseen consequences –Preparedness

“Acts of God” ? “Not only is the New Orleans damage not an act of God; it shouldn’t even be called a ‘natural’ disaster. These terms are excuses we use to let ourselves off the hook” Donald Kennedy. Editor-in Chief of Science