Seth Borenstein, Associated Press Yahoo News 14 Jan 10;
When it comes to natural disasters, the little island of Haiti seems to have a bull's-eye on it. That's because of a killer combination of geography, poverty, social problems, slipshod building standards and bad luck, experts say.
The list of catastrophes is mind-numbing: This week's devastating earthquake. Four tropical storms or hurricanes that killed about 800 people in 2008. Killer storms in 2005 and 2004. Floods in 2007, 2006, 2003 (twice) and 2002. And that's just the 21st Century run-down.
"If you want to put the worst case scenario together in the Western hemisphere (for disasters), it's Haiti," said Richard Olson, a professor at Florida International University who directs the Disaster Risk Reduction in the Americas project.
"There's a whole bunch of things working against Haiti. One is the hurricane track. The second is tectonics. Then you have the environmental degradation and the poverty," he said.
This is the 15th disaster since 2001 in which the U.S. Agency for International Development has sent money and help to Haiti. Some 3,000 people have been killed and millions of people displaced in the disasters that preceded this week's earthquake. Since the turn of this century the U.S. has sent more than $16 million in disaster aid to Haiti.
While the causes of individual disasters are natural, more than anything what makes Haiti a constant site of catastrophe is its heart-tugging social ills, disaster experts say. It starts with poverty, includes deforestation, unstable governments, poor building standards, low literacy rates and then comes back to poverty.
This week's devastating quake comes as Haiti is still trying to recover from 2008, when it was hit four times by tropical storms and hurricanes, said Kathleen Tierney, director of the University of Colorado's Natural Hazard Center.
And while there is bad luck involved, former top FEMA official Mark Merritt, president of the disaster consulting firm James Lee Witt Associates, says, "It's an economic issue. It's one of those things that feeds on each other."
Every factor that disaster experts look for in terms of vulnerability is the worst it can be for Haiti, said Dennis Mileti, a seismic safety commissioner for the state of California and author of the book "Disasters by Design."
Add to that the high population density in the capital, many of them migrants from the countryside who live in shantytowns scattered throughout Port-au-Prince.
"It doesn't get any worse," said Mileti, a retired University of Colorado professor. "I fear this may go down in history as the largest disaster ever, or pretty close to it."
For this to be the deadliest quake on record, the death toll will have to top the 2004 Asian tsunami that killed more than 227,000 and a 1976 earthquake in China that killed 255,000, according to the U.S. Geological Survey.
While nobody knows the death toll in Haiti, a leading senator, Youri Latortue, told The Associated Press that as many as 500,000 could be dead.
"Whether it comes in as No. 1, No. 2 or No. 3, only time will tell," Mileti said. "This is a major cataclysm."
Vulnerability to natural disasters is almost a direct function of poverty, said Debarati Guha Sapir, director of the World Health Organization's Centre for Research on the Epidemiology of Disasters.
"Impacts are not natural nor is there a divine hand or ill fate," Sapir said. "People will also die now of lack of follow-up medical care. In other words, those who survived the quake may not survive for long due to the lack of adequate medical care."
University of South Carolina's Susan Cutter, who maps out social vulnerability to disaster by county in the United States, said Haiti's poverty makes smaller disasters there worse.
"It's because they're so vulnerable, any event tips the balance," said Cutter, director of the school's Hazards and Vulnerability Research Institute. "They don't have the kind of resiliency that other nations have. It doesn't take much to tip the balance."
A magnitude 7 earthquake is devastating wherever it hits, Cutter said. But it's even worse in a place like Haiti.
One problem is the poor quality of buildings, Merritt said. Haiti doesn't have building codes and even if it did, people who make on average $2 a day can't afford to build something that can withstand earthquakes and hurricanes, he said. Poverty often is a major reason for poor infrastructure, Tierney said.
Then there's the deforestation that leads to mudslides and flooding because Haiti leads the hemisphere in tree-clearing, Merritt and others said. That causes erosion which worsens flooding. The trees are cut down mostly for cooking because of the poverty, Merritt said.
Another problem is the inability to prepare for and cope with disaster, said Merritt, who last fall started work to help train Haitians to prepare for disasters, including creating emergency response teams in a country that only has a couple of fire stations. It involved Haiti's small disaster bureau, the United Nations, Red Cross and other relief agencies and governments. The training manuals were still being translated from English to Creole when the earthquake hit, he said.
"If you look at neighboring Cuba, they have a very good emergency management infrastructure," Tierney said. "That's partly because of the way they organize the country from the block upward."
Another issue is that Haiti has been hurricane focused because quakes have been so rare in its history.
Until about a decade ago, scientists thought the north coast of Hispaniola was more prone to earthquakes. But work by Tim Dixon of the University of Miami found the southern fault zone, where Tuesday's quake occurred, was equally likely to produce temblors.
Scientists have known about the seismic threat for a while now, but Dixon said that doesn't help the Haitian government, which lacks the resources to quake-proof buildings and structures.
"This was not that huge of an earthquake, but there's been a lot of damage," he said. "It's the tragedy of a natural disaster superimposed on a poor country."
Haiti shares the island with the relatively richer Dominican Republic, which provides a good contrast when it comes to catastrophes, experts said.
Buildings in the Dominican Republic are stronger and withstand disaster better, Merritt said. Partly that's because it is a richer country with a more stable government.
The damage to Haiti is so devastating, so extensive that it offers a sense of hope in rebuilding, the experts said. Past disasters, including Hurricane Katrina, show that it is easier to put up new buildings than rebuild damaged ones, which is one reason why the wiped-clear Mississippi coast came back faster than New Orleans, Merritt said.
After the killer 1976 earthquake in Guatemala, houses were rebuilt with less vulnerable, lighter roofs and the entire region was designed to be less disaster prone, FIU's Olson said.
"Catastrophic disasters open a window of opportunity to fundamentally change how cities are rebuilt," Olson said. "If it's rebuilt in the same fashion (as it is now), our children are going to have this same conversation."
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Associated Press Writer Alicia Chang in Los Angeles contributed to this report.
Haiti Earthquake Science: What Caused the Disaster
Andrea Thompson, livescience.com Yahoo News 13 Jan 10;
The major earthquake that struck Haiti Tuesday may have shocked a region unaccustomed to such temblors, but the devastating quake was not unusual in that it was caused by the same forces that generate earthquakes the world over. In this case, the shaking was triggered by much the same mechanism that shakes cities along California's San Andreas fault.
The 7.0-magnitude Haiti earthquake would be a strong, potentially destructive earthquake anywhere, but it is an unusually strong event for Haiti, with even more potential destructive impact because of the weak infrastructure of the impoverished nation.
While reports from the ground on the effects of the quake are spotty because of downed communication lines, geologists can use worldwide measurements of the event as well as their general knowledge of how earthquakes work to piece together a picture of what happened in Haiti.
Sliding plates
Earthquakes typically occur along the jigsaw-puzzle pieces of Earth's crust, called plates, which move relative to one another, most of the time at an imperceptibly slow pace. In the case of the Haiti quake, the Caribbean and North American plates slide past one another in an east-west direction. This is known as a strike-slip boundary.
Stress builds up in points along the boundary and along its faults where parts of the crust stick; eventually that stress is released in a sudden, strong movement that causes the two sides of the fault to move and generate an earthquake. The fault system that ruptured to cause this quake is called the Enriquillo-Plantain Garden fault system.
Major earthquakes are rare in this part of the world in part because the Caribbean is a minor plate, with a fault system that isn't as long as, say, the San Andreas, which is at the boundary between two of the world's largest plates - the Pacific and North American plates.
The unusually high magnitude of Tuesday's quake for this region is part of the reason it has likely caused enormous damage to Haiti.
Intensity and infrastructure
Another factor in the damage that a quake can cause is it intensity. While magnitude is a measurement of how much energy is released by an earthquake, intensity is "simply an estimate or a measure of how strongly that earthquake was felt," said Don Blakeman, an earthquake analyst with the United States Geological Survey.
One factor that influences earthquake intensity is the distance to the epicenter of those who feel the earthquake's effects. In the case of the Haiti quake, the epicenter of the quake was only 10 miles (15 km) southwest of the capital Port-au-Prince and just 6.2 miles (10 km) below the Earth's surface, "which for earthquakes is very shallow," Blakeman told LiveScience.
"So everyone in Port-au-Prince is basically within 30 to 40 km [18 to 25 miles] of the earthquake," he added.
"The depth of this earthquake in Haiti was very shallow meaning that the energy that was released is very close to the surface," said Carrieann Bedwell of the USGS and NEIC.
In contrast, areas like the Fiji Islands in the South Pacific can experience earthquakes that originate hundreds of miles down in the Earth's crust, which would already put them hundreds of miles away from the earthquake, Blakeman explained. Earthquakes are much deeper in this the South Pacific because instead of two plates sliding past one another, one is descending deep into the Earth below the other, allowing earthquakes to originate much farther down below the surface. This is called a subduction zone.
Another unfortunate factor in the intensity equation for Haiti is the infrastructure involved.
The 1989 Loma Prieta earthquake that struck San Francisco just before Game 3 of the 1989 World Series was also about a 7.0-magnitude quake. While it killed scores of people and caused billions of dollars in property damage, the relatively high construction standards in the city kept the devastation much lower than what will likely be the case in Haiti.
Haiti is a poor country with lax building standards and high population density, which makes buildings more likely to crumble, according to Blakeman. "Unfortunately that's going to be a lot of the factor here," he said.
Experts have estimated that the death toll will likely reach into the thousands, with untold numbers homeless.
Another problem is the relative rareness of major earthquakes in the area coupled with poor public communication and education, which likely means that most Haitians were not prepared for such a disaster, as many Californians might be.
Waiting for answers
Information from the earthquake will help scientists better understand the future quake threat that exists for Haiti and the rest of the Caribbean by providing information that isn't available from the previously known major quakes in the region, which occurred in the 18th and 19th centuries.
Just how bad the destruction from the quake will be remains to be seen and likely will not be known fully for days, as reports trickle in from the crippled island nation. The United Nation and Red Cross have both mobilized emergency efforts.
"There is no doubt that we are facing a major humanitarian emergency and that a major relief effort will be required," said United Nations Secretary-General Ban Ki-moon.
Compounding the problems of the quake aftermath will likely be the numerous aftershocks that accompany any major earthquake. Though aftershocks are typically several orders of magnitude below the original temblor, they can still cause further damage, especially with the precarious building situation in Haiti.
The USGS has already measured more than 40 aftershocks above a 4.0 magnitude (including a 5.9 and 5.5 magnitude) and many more below that, Bedwell said. More aftershocks are anticipated in the coming days and weeks as the restive fault continues to react to the jolt that set it off in the first place.
"We like to think they are more repositioning of the faults in the area because of the larger earthquake," Bedwell said.
Haiti quake was nightmare waiting to happen: scientists
Richard Ingham Yahoo News 13 Jan 10;
PARIS (AFP) – The quake that hit Haiti on Tuesday was a killer that had massed its forces for a century and a half before unleashing them against a wretchedly poor country, turning buildings into death traps, experts said on Wednesday.
Scientists painted a tableau of horror, where natural forces, ignorance and grinding poverty had conspired to wreak a death toll tentatively estimated by Haitian Prime Minister Jean-Max Bellerive at more than 100,000.
The 7.0-magnitude quake occurred very close to the surface near the Haitian capital of Port-au-Prince, leaving almost no natural buffer to soften the powerful shockwave, these experts said.
"It was a very shallow earthquake, occurring at a depth of around 10 kilometers (6.2 miles)," seismologist Yann Klinger of the Institute of the Physics of the Globe (IPG) in Paris told AFP.
"Because the shock was so big and occurred at such a shallow depth, just below the city, the damage is bound to be very extensive," he said.
The US Geological Survey (USGS) said the quake occurred at 2153 GMT on Tuesday 15 kms (9.4 miles) southwest of Port-au-Prince.
It happened at a boundary where two mighty chunks of the Earth's crust, the Caribbean plate and the North America plate, rub and jostle in a sideways, east-west movement.
The USGS said the rupture occurred on the "Enriquillo-Plaintain Garden fault system," a slow-moving fault that last unleashed a large quake in 1860. Prior major events to that were in 1770, 1761, 1751, 1684, 1673 and 1618.
Sandy Steacey, director of the Environmental Science Research Institute at the University of Ulster in Northern Ireland, said the high death toll could be pinned overwhelmingly to construction.
"It's a very, very poor country without the building codes. Probably the fact that earthquakes (there) are very infrequent contributes in a way, because it's not a country that is focussed on seismic safety.
"Looking at the pictures, essentially it looks as if (the buildings are of) breeze-block or cinder-block construction, and what you need in an earthquake zone is metal bars that connect the blocks so that they stay together when they get shaken," said Steacey.
"In a wealthy country with good seismic building codes that are enforced, you would have some damage, but not very much."
French seismologist Pascal Bernard, also at the IPG, said that, given the nature of the fault, there was a "sizeable probability" that another large quake could occur in the same region within a matter of years.
Like other faults around the world, the Haitian crack is well known for domino activity, in which the release of pressure on one stretch piles on pressure in an adjoining stretch, bringing it closer to rupture.
In Haiti's case, the likeliest spot of a bust would be to the east of Tuesday's quake, Bernard said.
Asked whether another big quake was in the offing, Roger Searle, a professor of geophysics at Durham University, northeast England, said, "In the coming years, almost surely."
"We know pretty much where earthquakes occur, they've been mapped themselves and we can map faults and so on.
"The difficulty is it's very, very hard to predict when they will occur, because the network is so complex.
"It's a bit like making a pile of stones. You put more on the pile and it gets steeper and steeper and sooner or later the thing is going to collapse but you never which stone is going to do it and just where it's going to start to fail."
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