Deadly future
prompts planning

Figuring catastrophic risks
involves pitting costs
against benefits

Pop quiz.

Which of the following poses the biggest threat to American lives in 2005?

a) A tsunami
b) A terrorist attack
c) Traffic accidents
d) The flu
e) The bubonic plague

Welcome to the perplexing but increasingly pertinent realm of risk assessment.

The catastrophic Indian Ocean tsunamis of Dec. 26 have cast fresh attention on what emergency planners call "low-frequency, high-impact events" -- that is, disasters that happen very seldom but cause unimaginable havoc when they do.

How do we sensibly plan for a flood, earthquake or epidemic that is likely to occur once every 50 or 100 years?

"On the one hand, these extraordinary events happen seemingly at random, so they are nonroutine," says Brien Hallett, an associate professor with the University of Hawaii Program in Disaster Management and Humanitarian Assistance. "But if we can't predict the exact time and place, we can anticipate with absolute certainty that certain disasters will happen in certain places. For instance, there will be tsunamis in Hawaii."

A series of disasters in the 1990s, including Hurricane Iniki in Hawaii and Hurricane Andrew in Florida, prompted Congress to pass a law in 2000 requiring states and counties to plan ways to blunt the effects of natural hazards.

The State of Hawaii Hazard Mitigation Plan, approved in October by the Federal Emergency Management Agency, identifies risks to Hawaii that include hurricanes, tsunamis, flash floods, earthquakes, landslides, wild fires and droughts. FEMA also has approved mitigation plans for Honolulu and Kauai County, with the Maui and the Big Island county plans still pending, says Larry Kanda, of Hawaii Civil Defense.

In a perverse way, Hawaii enjoys an advantage because the potential disasters listed above have all happened here, many within memory. The difficulty lies in planning and formulating public policy for events for which there is no modern precedent.

For one thing, it's against human nature to worry about remote threats, at least one author argues. That's because humans evolved amid more pressing threats -- being eaten by a saber-tooth tiger, for instance.

"Human beings would not have survived in the dangerous circumstances of their ancestral environment had they been prone to let their attention wander from situations fraught with a high probability of immediate death," observes Richard Posner, a federal appeals judge in Chicago, in his new book, "Catastrophe."

"It is only when the overall probability of death declines, which happened after our biological evolution was essentially complete, that it becomes rational to focus on eliminating small risks," says Posner, who explores such nightmare scenarios as asteroid impacts, rapid global warming, and nanotechnology and subatomic physics experiments run amok.

But people ignore remote hazards at their peril, a lesson learned hard in the Indian Ocean last month, many scientists say.

ONE SUCH potential catastrophe is a massive landslide on the flanks of Mauna Loa, says Gary McMurtry, UH associate professor of oceanography. McMurtry and UH colleague Gerard Fryer have found evidence of such a landslide 120,000 years ago that generated a megatsunami that inundated the isles up to four miles inland.

But even a small landslide holds serious tsunami potential, he argues.

"What I've been trying to push is, we need to learn a lot more about flank collapse," says McMurtry. "We can learn enough about this situation so that we can give precursory warnings, at least to where people have their bags packed. The more we learn about the beast, the better."

Complicating the problem is that some geoscientists discount or ignore evidence they already have, he adds.

Japanese researchers, for instance, gave too little consideration to radon gas leaks from an aquifer that foreshadowed the disastrous Kobe earthquake of 1995, said McMurtry. There were similar clues at Galeras volcano in Colombia, said McMurtry, who attended a workshop on the threat not long before the deadly eruption in 1993. "They had precursor information that that volcano was about to blow, but the experts at that threat workshop didn't believe their own data."

Scientific disagreement has also hampered international efforts to mitigate the possible effects of global warming.

"One of my bits of philosophy is, you or I are not going to feel climate change by feeling the average global temperature change," says Eileen Shea, climate projects coordinator with the East-West Center. "You and I will feel it through extreme events."

Shea, who presented a report on El Nino this month to the American Meteorological Society meeting in San Diego, said planners must anticipate possible large-scale shifts in temperature and sea level.

"You need to be thinking about the long-term development decisions you are making in the context that the climate 50 years from now may not be what it is today," she says.

Michael Hamnett, a hazard mitigation expert who directs the University of Hawaii Research Corp., said FEMA and its state counterparts recognize today that development itself can be a big factor in disasters -- an important attitude shift from just 10 years ago.

Whether Indian Ocean communities wiped out by the tsunamis should rebuild differently -- or rebuild at all -- is a legitimate question for host governments and funding institutions, he suggests.

"Unfortunately, the orientation toward prevention hasn't caught on in places like the World Bank and Asian Development Bank, to the point where they would require risk and vulnerability assessments of a project," says Hamnett.

MITIGATION EFFORTS also can be colored by the emotions that accompany dramatic losses of life.

Fewer than 3,000 people died in the terrorist attacks of Sept. 11, 2001. Yet the 9/11 attacks generated billions of dollars in federal expenditures and the creation of a Cabinet-level department.

That same year, by comparison, about 55,000 Americans died from influenza, according to the Centers for Disease Control. Yet the federal government ran short of flu vaccine last fall.

Granted, the terrorist attacks represented an assault on the economy and collective psyche that no American wants repeated. But in terms of simple statistics, terrorist attacks do not represent anywhere near the largest threat to American lives. An unusually virulent flu strain likely would kill many times more; the 1918-19 global flu epidemic killed 20 million people, rivaling the estimated 25 million deaths from the plague in the 14th century.

It is conceivable that a huge tsunami or bioterrorists could kill, say, 200,000 Americans this year. But such an event would have to be repeated every four years to top the annual death risk from the flu and every five years to match the risk from traffic accidents: 42,000 deaths per year.

That makes (d), the flu, the answer to the quiz.

The possibility of a big space rock hitting the earth is even more remote than that of epidemics.

Yet the potential fatalities from an asteroid strike are so high that former UH astronomer David Morrison has calculated it represents the same mortality risk, on an annual basis, as an airplane crash or flood.

Since Morrison left UH in 1988 for the NASA Ames Research Center in California, that kind of risk calculus has gained much wider acceptance. The Faulkes Telescope on Haleakala joined late last year the growing international effort to spot rogue asteroids, of which about 30 to 40 are discovered every month.

"The intellectual trick is to absorb the fact that these are not random acts of God," says Hallett, the UH humanitarian assistance specialist. "They are routine acts of nature. And as soon as you can grasp that, you can start thinking about planning and mitigation."

At some point, however, Posner and others argue, the costs of mitigation can outweigh the benefits, even in terms of saving lives.

"No matter how much you plan or prepare or mitigate, a disaster will occur that will overwhelm you," predicts Hallett. "You cannot create a 100-percent secure environment with no hazards. It's just a basic fact of the human condition."