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Natural disasters took a deadly toll in 2008, killing more than 220,000 people and causing a total of $200 billion in damages–a 50 percent increase in costs over 2007. A new report sums up the damages wrought this year by weather and geology; the deadliest disaster was the cyclone that battered Myanmar in May, killing an estimated 130,000 people and causing losses of $4 billion, and the costliest was the earthquake that struck China’s Sichuan province, killing an estimated 70,000 and causing losses of $85 billion.

The new figures come from an annual assessment of global damages by the reinsurance giant Munich Re, which offers backup policies to companies writing primary insurance policies. Reinsurance helps spread risk so that the system can handle large losses from natural disasters [AP]. Munich Re has a financial interest in understanding global weather patterns, and board member Torsten Jeworrek says the uptick in losses from natural disasters is another indication that global warming is already having widespread effects. “Climate change has already started and is very probably contributing to increasingly frequent weather extremes and ensuing natural catastrophes,” he said [BBC News].

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While Indonesia is still rebuilding following the devastating 2004 earthquake and tsunami that killed more than 130,000 people on the island of Sumatra alone, scientists are warning that several other major earthquakes are likely to occur in the region over the next decades. A new study examined the growth records of coral reefs off the coast of Sumatra, and say they show evidence of repeated bursts of earthquakes that relieve pressure on the Sunda fault. A shock in 2007 may be the beginning of a new cycle, researchers say.

Says study coauthor Kerry Sieh: “If previous cycles are a reliable guide we can expect one or more very large west Sumatran earthquakes … within the next two decades” [Reuters]. As if to illustrate the point that the Indian Ocean is seismically active, reports are coming in that a 5.9 magnitude earthquake struck last night off the coast of Sumatra; happily, there have been no reports of casualties or damages, and authorities say there is no risk of a tsunami.

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Two groups of geologists have found evidence that the Indian Ocean tsunami that devastated coastal towns in Southeast Asia in 2004 wasn’t the first massive wave to pummel those shores, but the last tsunami of equivalent size occurred about 600 to 700 years ago. That long gap might explain how enough geological stress built up to power the huge undersea earthquake that launched the killer waves four years ago, researchers said [AP].

One group of researchers took sediment samples on a barrier island off the west coast of Thailand, while the other group dug into the soil in a northern region of Sumatra. The surge of a tsunami brings with it a great deal of sediment that rushes inland; the bigger the tsunami, the deeper and further inland the layer of sediment it leaves behind. In locations where those deposits aren’t disturbed by wind or running water, they can be used as a historical record of tsunami after more layers are added later [BBC News].

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In a new study, researchers looked at the role of cyclones in Earth’s carbon cycle. They found that cyclones (an umbrella term for hurricanes, typhoons, and tropical storms) can transfer terrestrial organic carbon, in the form of plants, soil, and fossils, to the bottom of the oceans and prevent it from entering the atmosphere. In just a few days a single typhoon can dump the same amount of carbon to the bottom of the ocean as an entire year of rain. The storms do this by ripping mud and decaying vegetation off the land, and flushing it down rivers in huge floods and out to sea [New Scientist].

The study, published in Nature Geoscience [subscription required], conducted on the LiWu river in Taiwan, focused on how cyclones sequester carbon rather than how much carbon they bury. Nevertheless, the researchers warn that the amount of carbon sequestered by cyclones is a pittance compared to the amount of carbon generated by human activity. “The current amount of carbon dioxide building up from manmade sources is about 100-1,000 times faster than this carbon (burial) from the interaction between the cyclones, erosion and forests,” said Robert Hilton of Cambridge University who was one of the authors. “In terms of the manmade carbon cycle this is not going to save us. But it illustrates that the earth has natural ways of dealing with carbon dioxide,” he said [Reuters].

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The May earthquake in China’s Sichuan province that killed 70,000 people may lead to further destruction. According to a new seismic study, the magnitude 7.9 earthquake in May increased the stress on nearby faults, and therefore heightened the risk of further quakes. Stress on the nearby Kunlun, Xianshuihe and Min Jiang faults has increased, they say, doubling the risk that one of them will unleash a magnitude 6.0 or 7.0 tremor in the next decade [Discovery News].

Those three nearby faults are now under more stress because of a domino-like effect where the movement of one piece of Earth’s crust forces another piece to move up, down and away, geophysicists reported. “One great earthquake seems to make the next one more likely, not less,” said [study coauthor] Ross Stein of the U.S. Geological Survey. “We tend to think of earthquakes as relieving stress on a fault. That may be true for the one that ruptured, but not for the adjacent faults” [Reuters].

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In the destructive heart of hurricane season, climate scientists have come out with some alarming news: the most powerful storms have gained wind strength over the past 25 years as a result of gradually warming ocean waters, and global warming is likely to continue that trend. It’s hardly welcome news, as Gulf Coast residents are still recovering from this week’s close call with Hurricane Gustav and Caribbean islanders are warily eyeing several new tropical storms gaining strength over the Atlantic.

The new study is likely to renew the debate over global warming’s effect on major storms: [T]here has been controversy about whether these hurricanes will get more intense and numerous, with many claiming the data are not good enough to discern a real trend upwards in recent years…. Today’s study, by Prof James Elsner of Florida State University, concludes that the strongest tropical cyclones - the general term for intense storms such as hurricanes and typhoons - are getting stronger, with the greatest increase recorded in the North Atlantic and northern Indian oceans [Telegraph].

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In a congressional hearing yesterday, a supplier of the “FEMA trailers” used after Hurricane Katrina admitted that the company has known for years that the trailers contained dangerous levels of formaldehyde. But the chairman of Gulf Stream Coach said his company failed to disclose to Hurricane Katrina evacuees or the government its internal findings that formaldehyde in some units exceeded a federal health standard by as much as 45 times in 2006 [Washington Post].

Gulf Stream received over $500 million from the Federal Emergency Management Agency (FEMA) for 50,000 trailers that housed displaced Gulf Coast residents after the devastating 2005 hurricanes. But Gulf Stream chairman Jim Shea deflected blame for the evacuees’ chemical exposure to FEMA, saying that the agency turned down the company’s offer to conduct thorough tests on the trailers.

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Researchers working at California’s San Andreas Fault say they detected subtle geological shifts that occurred hours before two small earthquakes, raising the possibility that scientists could eventually develop an early warning system to get people out of harms way well before the earth started to tremble.

“If you had 10 hours’ warning, from a practical point of view, you could evacuate populations, you could certainly get people out of buildings, you could get the fire department ready,” said co-author Paul Silver of the Carnegie Institution for Science, Washington. “Hurricane [warnings] give you an idea of what could be done” [BBC News].

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Brace yourself. That’s the underlying message in a new report from the federal government, which predicts more extreme weather events in North America as a result of human-caused global warming. According to the report, in the coming decades we can expect more droughts, heavy rainfall, heat waves, and hurricanes; these weather events will be both more commonplace and more intense.

The report, from the Bush administration’s U.S. Climate Change Science Program, says these changes are already apparent. Elevated temperatures in recent decades already have led to more intense rainstorms in the Midwest, Northeast and Mid-Atlantic regions, said Thomas Karl, co-chairman of the report. “The probability of heavy downpours is increasing, which leads to events like what we’re seeing in the Midwest,” said Karl [Bloomberg], referring to the heavy floods that inundated Iowa and Missouri in the past week.

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Aftershocks sent ripples of fear through China yesterday and today, as engineers and army officials struggled to drain the “quake lake” formed by the massive May earthquake, when rubble from a landslide dammed the Tongkou River in southwest China.

The lake’s water level has been rising steadily, and officials worry that another quake could burst the dam, threatening more than 1 million people downstream. The government has already evacuated 250,000 people.

As the lake is in a remote mountainous region accessible only by foot and by helicopter, the army has airlifted in construction equipment, explosives, and personnel. The teams have already dug out a spillway to safely drain the water and reduce pressure on the dam, but observers say it’s not working well enough.

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