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The tops of tsunamis glow red, it turns out

So how does a tsunami register in the atmosphere hundreds of miles above? On the ocean, tsunamis can move many hundreds of miles per hour, but until they get close to the shallows created by a landmass they alter the ocean very little, outwardly showing themselves as a wave just one inch high. But that added inch of ocean pressure pushes up on the atmosphere ever so slightly, and if you know where to look you can see its impact in the sky.

Where you look is specifically about 155 miles straight up in the ionosphere. Here, the air is much thinner and the amplitude of that upward-traveling pressure wave is able to grow. It’s also here that the pressure interacts with the charged plasma of the Earth’s upper atmosphere, creating a faint red glow.

You can’t see the glow with the naked eye, and in fact you can only see it from the ground with with the right kind of instruments (in this case, the Cornell All-Sky Imager at the Air Force Maui Optical and Supercomputing Station atop Haleakala) on a clear night with no moon. But a satellite in stationary orbit over the Pacific packing the same kind of instrument could likely monitor for tsunamis continuously.

That could be a big step toward a realistic tsunami prediction network. After all, this first-ever observation of tsunami-derived ionospheric “chemiluminesence” preceded the wave’s arrival in Hawaii by roughly an hour.

[Honolulu Star Advertiser]

The river is trying to escape the path that humans have determined for it, and increasingly it is doing so

But while the 2011 floods are the worst in years, for many places they're not the worst in that many years. The Big Muddy is topping its banks and barriers more frequently and with greater consequences than flood models tend to predict. There are several reasons for that depending on who you ask, but regardless of whether it’s global warming, bad flood modeling, or simple statistical anomaly, one thing is abundantly clear: the mighty Mississippi wants out of the path that humans have determined for it, and it is increasingly finding ways to escape.

The Army Corps of Engineers often speaks in terms of 100-year or 25-year floods (a somewhat confusing nomenclature that means a flood of a given magnitude has a 1-in-100 or a 1-in-25 chance of occurring in a certain year, respectively), but since 1993’s devastating Midwestern floods, some places in the region are seeing 10- and 25-year events several times in a single decade.

From an engineering and infrastructure standpoint, this is becoming a serious problem. Fighting back the waters is an ongoing fight--and if one were to judge from the Corps’ decision to blow some levees in Missouri earlier this month to relieve pressure upstream, it’s a fight that we aren’t necessarily winning.

Click to launch the photo gallery
Some residents are taking civil engineering into their own hands. Click through the gallery to see some DIY efforts to beat back the floodwaters.

“The river has a job to do,” says Robert Criss, a professor of Earth and planetary sciences at Washington University in St. Louis. “Its job is to move water and dirt to the Gulf of Mexico. It has adjusted its morphology in the most efficient way that it can to do that. But of course we think we know better, so we’ve changed that.”

Criss refers to the complex system of levees, dikes, spillways, and locks, that have been constructed along the length of the river to make it straighter, deeper, and more conducive to moving goods along its length. From a geoengineering standpoint, the Mississippi is a modern marvel, a massive case of humans bending nature to their will through clever engineering and lots of concrete. But the river is pushing back.

Take the lower Mississippi, right at the point where it hits the homestretch to the Gulf. The river wants to take a new path to the Gulf, one that is 150 miles shorter. Doing so becomes a more tempting proposition for the river with every passing year. As the river carries more and more sediment downriver to the Gulf, its path grows longer and longer, forcing it to deposit more sediment upstream to maintain sufficient force to make its way to the Gulf.

This puts additional stress on the river system, stress that would be relieved if the river turned west and down through the Atchafalaya River, which connects to the Mississippi some 45 miles north-northwest of Baton Rouge, and headed on out to sea. Holding it back is the Army Corps of Engineer’s Old River Control Structure (completed in 1963, it is indeed old). If the Old River Control Structure were to fail--and infrastructure does fail, as Americans learned the hard way when Katrina hit--the map of the Mississippi Delta would be redrawn in a matter of hours, with devastating consequences.

Last week the executive director of the Port of New Orleans said that closure of the Mississippi due to the most recent flooding would cost nearly $300 million per day. If the main thrust of the Mississippi took the Atchafalaya route and bypassed New Orleans to the west, the city would need a new livelihood and America would need a new port city and all the infrastructure and pipeline that comes with it. That’s not even counting the losses from the areas that would flood and become unusable through the Atchafalaya basin.

The results would be economically crippling, at least for several years. And the same argument can be made all along the entire 2,300-mile length of the river (and along every major waterway in America). So we instead must keep building, and occasionally making undesirable tradeoffs, like the one the Corps of Engineers was forced to make two weeks ago when it blew levees along the Mississippi to save the town of Cairo, Ill., flooding 130,000 acres of Missouri farmland and devastating entire agricultural communities instead.

“Do you keep building the levees, etc., etc., and spending all this money?” says Dr. Thomas Zimmie, a professor of civil and environmental engineering at Rensselaer Polytechnic Institute. “In most cases, you don’t have much choice. There are more than 100,000 miles of levees in the U.S.,” almost every one of them protecting some enclave of residential, agricultural, or commercial life.

Zimmie was part of the team of engineers that assessed New Orleans’ broken levees for Congress in the aftermath of Katrina, and he heard the criticisms bouncing around the national conversation after that storm saying New Orleans, a city below sea level, was a lost cause. But all sentiments aside, from an infrastructure point of view the rebuilding of the city--and its levees--was never in question. “You can’t abandon New Orleans,” he says. “It’s a major port.”

There’s no outright way to fix this push-pull between human development and the river, but Robert Criss, the scientist, thinks it’s possible to strike a kind of compromise.

“The levees are actually too high,” Criss says. “We need lower levees, particularly those with agricultural land behind them, and those lower levees need more gates on them.” The idea, he says, is to keep levees from overtopping, when the water tends to surge more like a dam break, scouring away topsoil and destroying farmland (and anything else in its path).

“Rather than having these levees catastrophically fail and having these tsunamis of high-energy, turbulent water scouring the farms, you crank the gates open, let the waters flow gently over the farmland,” he says. “You create wetlands for the year and those farmers can be compensated for floodwater storage the same way they are sometimes compensated for letting their land lie fallow.”

It’s a system of controlled flooding, and while it’s not a perfect compromise, it would mitigate catastrophic inundation and--in the worst cases--destruction of critical infrastructure. Zimmie likes the notion, but he’s less optimistic that such a system could be implemented.

“In theory I agree with that answer, but when you start looking into how to do it it’s not that easy,” he says. “When you start saying ‘okay, we’re going to flood this and not that,’ it’s not a real practical answer as far as I’m concerned. When you get into the nitty-gritty, it starts to get really tough.”

So the Army Corps of Engineers will keep building--and occasionally blasting--because what else can it do at this point? The river wants to change course, and we’re going to do our best to ensure that it doesn’t. Until, eventually, it does.

“The Atchafalaya distributary is going to eventually win, and the river is going to go that way,” Criss says. “Some flood will eventually undermine these structures. This is a geologic inevitability.”

Monirobo can withstand radiation that humans cannot handle

The hurricane house, the seismograph camera, the forest-fire-fighting dirigible, and more technologies developed for reducing the consequences of natural disasters

Sturdy skyscrapers, a capable warning system and disaster training didn't come from nowhere, though. As sad as it is to admit, most disaster-prone countries had to learn from destruction in order to improve their technology. We've collected several examples of early disaster-fighting tech from the Popular Science archives.

Click to launch the photo gallery.

We begin in the fall of 1919, just after World War I, when dirigibles glided across national forests in search of fires. After the war, scores of airplanes and zeppelins were commissioned to join horseback-riding firefighters to extinguish the flames consuming our trees. Meanwhile, on the other side of the world, Japan was about to suffer an earthquake that would kill an estimated 140,000 people. After the 1923 Great Kanto Earthquake and tsunami destroyed Tokyo and Yokohama, scientists collaborated to devise methods that would reduce the body count in future disasters. Japanese scientists simulated earthquakes on scale models of buildings to see what kind of engineering held up, while an American professor proposed installing ball bearings within houses for stabilization.

Meanwhile, laypeople did everything they could to protect themselves from disasters. One architect built a teardrop-shaped "hurricane house" that turned with the wind during a storm, while businesses sold the all-steel cyclone cellar, which could be delivered in one piece, no assembly required. Simply dig a hole in your front yard, embed the cellar below, and hop in when the winds begin to stir.

See more technologies by browsing through our gallery.

The map above is a model of wave heights, generated at the Center for Tsunami Research at the NOAA Pacific Marine Environmental Laboratory. Wave energy dissipates over longer distances, so Hawaii and the west coast didn’t see the devastating waves that inundated Japan already, but the scope is still incredible — the entire Pacific Ocean is impacted. Waves were lower in areas where the ocean floor is deeper.

The animation below shows the tsunami as it propagated from the earthquake’s epicenter, about 80 miles off the Japanese coast at a depth of around 15 miles. The ripples’ calm, slow spread belies their destructive force.

The death toll keeps rising, now said to be more than 1,000, according to news reports. USA Today has compiled this list of ways you can help.

Aftershocks are adding to the problems, with almost 100 reported as of 1 p.m. EST Friday.

One of the ten largest earthquakes ever recorded in the world

Google’s Person Finder, also used in the recent New Zealand earthquake, is only as effective as the numbers of people using it — but it’s catching on quickly, with about 6,900 records as of 10:30 a.m. EST. Users can enter a name in English or Japanese and search for missing persons, or post updates about people who you know are safe. It also aggregates other disaster bulletin boards erected by Japanese companies.

Similarly, a local developer in Tokyo put up an Ushahidi crisis platform, which is collecting information about the locations of trapped people and unsafe buildings. People can find out where to find help or a pop-up hospital, according to GOOD. The platform was used to help relief workers in Haiti.

Though Japan is by far the hardest hit, 20 countries including the U.S., Canada, Russia, the Philippines and several Pacific island nations are under tsunami warnings. Hawaii’s Pacific Disaster Center is posting updated tsunami warnings and a map showing the dangers facing each of the state’s islands.

The Hawaii chapter of the Red Cross is using Twitter to post tsunami warnings and potential evacuation efforts.

And a United Nations satellite-monitoring group might also be activated, reports Fast Company.

The earthquake is among the top 10 largest ever recorded, according to U.S. Geological Survey seismologists. The devastation is still unfolding, with fires raging, widespread blackouts and a devastating tsunami. Workers at a nuclear plant in Fukushima prefecture are having trouble cooling off the reactor, and the area is being evacuated; hundreds of people are confirmed dead in the wake of the tsunami; waves of mud inundated farmland; and transportation has ground to a halt.

Meanwhile, disaster-relief agencies are starting to mobilize and accept donations. The Defense Department is readying American forces in the Pacific to help, AP reported.

TwinSat, as the project is known, involves two satellites cruising a few hundred miles apart in a polar orbit. One satellite will be roughly the size of an old vacuum-tube style television set and the other smaller than a shoebox.

The duo will be looking for subtle but detectable electromagnetic signals that can be gleaned from the upper atmosphere. These signals are the result of stress building up in the Earth, slight changes in the Earth’s magnetism that could be the telltale signs that tremors are imminent. These kinds of signals were picked up in the days leading up to the devastating Haiti ‘quake last year, though they weren’t parsed and analyzed until later.

Scientists think that if they knew what kinds of electromagnetic signals predate earthquakes, they could use them as predictors of when and where big ‘quakes are likely to strike perhaps days or weeks beforehand. Of course, the only way to categorize those signals is to put sensors in place that can identify them and wait for earthquakes to happen.

That’s TwinSat’s role; the tandem satellite setup will monitor seismically active zones like Iceland and eastern Russia for the signs that predate earthquake activity. If it works--and that’s a significant “if”--an array of the sats could be deployed to monitor the entire Earth, ensuring disasters like the Haiti earthquake exact a minimal human toll. TwinSat will launch in 2015.

[The Independent]