Mantoloking Bridge, Northern New Jersey, March 18, 2007
Mantoloking Bridge after Superstorm Sandy, October 31, 2012
Superstorm Sandy wreaked havoc on the East Coast last week. Camera crews and smartphone-toting locals chronicled the storm’s devastation on the street. These aerial photos, taken 7,500 feet above the ground, demonstrate the destruction on a larger scale. Just north of the spot where Sandy came ashore, the Mantoloking Bridge used to connect this barrier island to mainland New Jersey. The bridge was only two years old when the first picture was taken, in March 2007, but since the storm has washed away much of this former island, it has become, quite literally, a bridge to nowhere.
Images courtesy of the NOAA Remote Sensing Division, NASA.
The wave that washed over the eastern coast of Japan was more than 130 feet high.
You would expect that a disaster of the magnitude of the Tohoku tsunami and earthquake, which killed 15,000 people and caused about $210 billion in property damage, would have people feeling more apt to evacuate when another killer wave approaches. But, strikingly, scientists who interviewed Japanese people a year before the event and afterwards found that the size of the waves they would think dangerous enough to flee had grown. As Adam Mann writes at Wired, people had stopped recognizing the height at which a wave becomes dangerous:
The National Palace in Port-au-Prince
after the 2010 Haiti earthquake
What’s the News: To dampen structural vibrations from earthquakes, engineers often place a flexible layer of rubber bearings in between buildings and the soil. Now, scientists are learning that Mother Nature uses a similar technique. A research team has found that a buried layer of mangrove in the Caribbean island of Guadeloupe absorbs earthquake energy, shielding the above ground from soil liquefaction. This discovery could be exploited to help protect new buildings in the Caribbean islands.
A house decimated by the 2010 earthquake in Chile.
What’s the News: Enormous earthquakes are rare; there have been only seven quakes with a magnitude 8.8 or above since the start of the 20th century. Of those seven quakes, three of them have happened in the past seven years: off the coasts of Indonesia in 2004, Chile in 2010, and Japan last month. Some researchers think this earthquake cluster marks the start of a period of megaquakes, while others believe that the earthquake cluster is simply a statistical fluke, with these unusually massive quakes just happening to occur within a short amount of time, according to recent analyses (PDF) of Earth’s earthquake history presented at the Seismological Society of America’s annual meeting last week.
Reactor 3 at the Fukushima Daiichi plant, on March 24
What’s the News: A non-peer-reviewed study (pdf) publicized last week by radioactivity-detection expert Ferenc Dalnoki-Veress suggests that nuclear fission reactions continued at Japan’s Fukushima nuclear power station well after the plant’s operators had allegedly shut down the reactors there. The paper says there may be what are called “localized criticalities” have occurred in the plutonium and uranium left in the reactors—little pockets of fuel that have gone critical, propagating the nuclear chain reaction and generating potentially harmful radiation. The existence of criticalities is controversial: some researchers say there are certainly none; Dalnoki-Veress himself says it’s only a possibility.
Image: flickr / daveeza
Oil refineries aflame. Train tracks twisted like string. Buildings ripped from their foundations. Japan’s 8.9-magnitude earthquake has left its mark, especially in the expected death toll of over 1,000 people. This video roundup shows the science behind what happened today in Japan.
Why (Most) Buildings Didn’t Crumble
The death toll is estimated around 1,000, which is bad enough, but it would have been much higher without good engineering, mandated by strict building codes. But these codes haven’t been strict for long. In the 7.3-magnitude Kobe earthquake in 1995, 6,500 Japanese people died, and engineers looked on in horror as many buildings came crashing down; the most deadly ones were built before 1981, when building standards were still lower.
The Kobe tragedy, says The Telegraph‘s Peter Foster, compelled Japanese officials to tighten building regulations for residential offices and transportation infrastructure. Engineers made buildings “earthquake proof” by outfitting them with “deep foundation and massive shock absorbers that dampen seismic energy,” and by enabling the bases of buildings to move “semi-independently to its superstructure, reducing the shaking caused by a quake.” Skyscrapers now sway during an earthquake but don’t collapse, Foster says, and that helps explain why damage to buildings in Tokyo was kept to a minimum this time around. [The Atlantic Wire]
Why Couldn’t Geologists Predict It?
Japan’s massive earthquake today may be over, but we’re still feeling the effects, from nuclear reactor scares in Japan to tsunami warnings along the entire west coast of North America, from Mexico to Alaska’s Aleutian Islands. Much is still unknown about this earthquake, including official destruction assessments and total death tolls, but here’s what we do know:
Two preliminary earthquakes with magnitudes of 7.2 and 6.3 struck off the coast of Honshu, Japan, the day before the major blow: This 8.9-magnitude quake—the largest in Japan’s recorded history—struck at 2:46 pm local time on Friday, its epicenter located about 231 miles northeast of Tokyo at a depth of 15 miles. Even after this large one, over thirty aftershocks—the strongest measuring 7.1 in magnitude—continued to batter the island nation.
The Immediate Effects
Fires and collapsed buildings were the main cause of injuries and death early on, from conflagrations sweeping an oil refinery in Chiba prefecture near Tokyo to the roof collapsing during a graduation ceremony in Tokyo. But fears soon centered on Japan’s nuclear facilities: Four power plants successfully shut down, but one experienced problems:
According to Nature’s Tokyo correspondent, David Cyranoski, Japanese media are reporting that the emergency core cooling system (ECCS) at the Fukushima #1 plant is not working due to a loss of electrical power, and problems with the backup diesel generator. The reactor is currently relying on an alternate cooling system that circulates water using a pump system. This system can operate for about 7 to 8 hours. According to the Nuclear and Industrial Safety Agency of the government’s industry ministry, this is the first time in Japan that the ECCS of a nuclear power station has not functioned. [Nature]
The local governments near the Fukushima plant urged the area’s 2,000 residents to evacuate, though no leaks have been detected and the Japan Atomic Industrial Forum assured everyone (pdf) that Fukushima reactor’s core “still has a sufficient amount of water for cooling, with no danger of the nuclear fuel being exposed”.
Why It Could Have Been Worse
At least 65 people died in an earthquake that struck New Zealand’s second-largest city, Christchurch, yesterday. As the city digs out from the rubble created by the magnitude 6.3 quake, some there are worried the death toll could climb into the hundreds. And as seismologists unravel the details, it’s becoming clear why this quake was so much deadlier than previous seismic events in New Zealand.
Photographs and video from Christchurch, a metropolitan area of nearly 400,000 residents, showed people running through the streets, landslides pouring rocks and debris into suburban streets and extensive damage to buildings. Witnesses told of watching the spire of the iconic Christchurch Cathedral come crashing down during an aftershock. One witness called it “the most frightening thing of my entire life,” and television footage showed a person clinging to a window in the cathedral’s steeple. [The New York Times]
One cannot look at a single storm, flood, or drought and say conclusively, “climate change caused that.” But what researchers are attempting to do lately is climate change risk assessment—figuring out how much more likely severe events may become as our world continues to warm up. Two new studies in Nature today try to do just that with heavy rains and flooding, saying definitively that warm temperatures make these events more likely.
More-localized weather extremes have been harder to attribute to climate change until now. “Climate models have improved a lot since ten years ago, when we basically couldn’t say anything about rainfall,” says Gabriele Hegerl, a climate researcher at the University of Edinburgh, UK. [Nature]
Hegerl and climate researcher Francis Zwiers were authors on study number one, a broad-based look at how much humans are contributing to intense precipitation events in the Northern Hemisphere. The simple physics of it makes sense: warmer air can hold more water. To show a link, however, the researchers pulled together a half-century of rainfall records, which they compared to the results of eight different climate models.
Richard Allan, a climate scientist at the University of Reading in England who was not part of the study, called the method employed by Zwiers “very rigorous.” He added, “There’s already been quite a bit of evidence showing that there has been an intensification of rainfall” events across the globe. But until now “there had not been a study that formally identified this human effect on precipitation extremes,” Zwiers said. “This paper provides specific scientific evidence that this is indeed the case.” [Washington Post]