We CAN Do Something About Tsunami. The ferocious tsunami that devastated Japan’s coast is a tragic reminder that we have an uneasy relationship with our oceans. While we can’t prevent earthquakes, we can minimize at least some of the damage from tsunamis on American shores by dealing with climate change and rising ocean levels now.
March 20th marked the beginning of National Tsunami Awareness Week. We will continue to hear more about the tragedy in Japan and about which preparations worked or which ones didn’t. We will hear much more about awareness and warning systems. Those discussions also need to include the ongoing threat from a rise in ocean levels. When the tsunami swells ripped toward the west coast of North America at hundreds of miles an hour two weeks ago, it was only luck of timing that they coincided with low tide in the areas of California that were the hardest hit, lessening the tsunami’s impact. What can humans do about things that appear to be massive forces of Nature?
The lessons here are many. Japan Get Battered By 572 EQs in 8 Days. There have been plenty of reports of the aftershocks that keep rattling Japan and hampering relief efforts, but this is astounding. Click on the Japan Quake Map above and watch a sequential plot of all 572 earthquakes that have measured higher than a 4.0 on the Richter since last Friday. On the map, the size of the ring indicates the magnitude, and the color shows how deep the earthquake occurred.
You can also play with the settings a bit and limit the plots you see based on minimum magnitude or date. The sequence starts off very slow, with three medium-sized earthquakes all close to 5.0 on the Richter, then a long twelve hours before the massive 9.0 magnitude quake that lights up the entire screen and sets off an absolutely stunning sequence. You can practically feel the Earth's crust settling as you watch the circles explode. So far there have been 38 earthquakes measuring higher than 6.0 on the Richter, seven higher than 6.5, and three higher than 7.0. Japan EQ- Not the "Big One? Though Friday's Japan earthquake—which spawned a tsunami and damaged a nuclear power plant—was the largest to strike the country since the dawn of modern seismology, it wasn't the long dreaded "big one," experts say. Not because the magnitude 9 earthquake wasn't big, but because it was in the wrong place. (See Japan earthquake and tsunami pictures.) Seismologists have long predicted that the big one would probably be a repeat of the 1923 Kanto earthquake, which occurred in a dangerous fault zone close to Tokyo and killed an estimated 142,000 people.
Japan is a tectonically complex zone where three major plates, the Pacific plate, the Okhotsk plate, and the Philippine plate are all ramming into each other. (Learn more about tectonic plates.) The 1923 earthquake—estimated to have had a magnitude of between 7.9 and 8.4—came from the collision between the Philippine plate and the islands of Japan, in a fault zone known as the Sagami Trough, offshore from Tokyo. Larger Earthquakes Predicted. Japan EQ– Reading The Signals. At the Top of the World.The massive 9.0 M earthquake at Tohoku, Japan, 11. March 2011 literally shook the entire planet. The signals were read even at the top of the world, close to the north pole. Read on to learn about earthquake and tsunami observations in general before you take a look at the unique earthquake recordings from the high-north. by Bente Lilja Bye and Ove Christian Dahl Omang Ny-Ålesund Geodetic Laboratory, Svalbard, Norway. After the 2004 Indian Ocean tsunami the international community stepped up its efforts on developing and building early warning systems.
In Japan there are a number of dense monitoring networks, like the national seismic networks that we see on this map. In Haiti Earthquake, science, early warning and mitigation a general description of warning systems is presented. The Tokohu-oki earthquake 11th March 2011 caused a massive tsunami that devastated the shores of Japan's Honshu island. Here we see the signal with greater resolution. Japan EQ: How Tokyo got an 80-sec. head start. Residents of Tokyo likely had about 80 seconds of warning before a devastating quake rumbled through the city after striking 373 kilometers away, off Japan's northeast coast, thanks to a new early warning system. But tsunami alerts take longer to generate, giving just minutes of warning before the waves first struck the coast—a reflection of the differing technologies needed to detect earthquakes and calculate their impacts, researchers say.
Skip to next paragraph Subscribe Today to the Monitor Click Here for your FREE 30 DAYS ofThe Christian Science MonitorWeekly Digital Edition Japan has the world's most advanced earthquake early-warning system, with more than 1,000 seismographs scattered over the country. The seismometers detect the first evidence of a quake—P-waves, which have short wavelengths and generally do little damage—and calculate the location of the epicenter. RELATED: The 10 nations most reliant on nuclear power The quake struck at 5:46 GMT. IN PICTURES: Japan's 8.9 earthquake. Liquefaction from the Sendai EQ. Understanding Japan’s Nuclear Crisis. By John Timmer, Ars Technica Following the events at the Fukushima Daiichi nuclear reactors in Japan has been challenging. At best, even those present at the site have a limited view of what’s going on inside the reactors themselves, and the situation has changed rapidly over the last several days.
Meanwhile, the terminology involved is somewhat confusing—some fuel rods have almost certainly melted, but we have not seen a meltdown; radioactive material has been released from the reactors, but the radioactive fuel currently remains contained. [partner id="arstechnica" align="right"] Over time, the situation has become a bit less confused, as cooler heads have explained more about the reactor and the events that have occurred within it. What we’ll attempt to do here is aggregate the most reliable information we can find, using material provided by multiple credible sources.
Inside a Nuclear Reactor Nuclear reactors are powered by the fission of a radioactive element, typically uranium. Japan Quake Epicenter Was in Unexpected Location. Japan has been expecting and preparing for the “big one” for more than 30 years. But the magnitude-9.0 temblor that struck March 11 — the world’s fourth biggest quake since 1900 — wasn’t the catastrophe the island nation had in mind. The epicenter of the quake was about 80 miles east of the city of Sendai, in a strip of ocean crust previously thought unlikely to be capable of unleashing such energy. “This area has a long history of earthquakes, but [the Sendai earthquake] doesn’t fit the pattern,” says Harold Tobin, a marine geophysicist at the University of Wisconsin-Madison.
“The expectation was high for a 7.5, but that’s a hundred times smaller than a 9.0.” Understanding where big earthquakes will emerge is extraordinarily difficult, and nowhere more so than Japan. The Sendai earthquake occurred at the Japan Trench, the junction of the westward-moving Pacific Plate and the plate beneath northern Japan. See Also: History Of Tsunami. Hide captionIn Japan, the first recorded use of the word "tsunami" occurred well over 1,000 years ago. Tuesday, a boat lay aground after being washed inshore near Sendai. Fred DuFour/AFP/Getty Images In Japan, the first recorded use of the word "tsunami" occurred well over 1,000 years ago. Tuesday, a boat lay aground after being washed inshore near Sendai. The word "tsunami" is originally a Japanese word, but today it's commonly used in English. The first English use of the word happened more than 100 years ago, says linguist Ben Zimmer, of the Visual Thesaurus.
"There was reporting in the National Geographic Magazine, and it said, 'On the evening of June 15, 1896, the northeast coast of Hondo, the main island of Japan, was struck by a great earthquake wave,' " Zimmer says, "and then it explained that the Japanese term for this was 'tsunami From that first mention, the term became more widespread — especially after the disaster that devastated Indonesia in 2004. A Question Of Accuracy. Japan: The ‘Big One’ hit, but not where they thought it would. But the grinding plates of the earth move in mysterious ways, and Friday the largest recorded earthquake in Japan’s history — a stunning magnitude 8.9 on the short list of most violent events since the dawn of seismology — hit about 230 miles northeast of Tokyo, generating a tsunami that within minutes socked the coast of Honshu, Japan’s largest island.
The epicenter of the earthquake was about 15 miles below the sea floor and about 80 miles east of the coastal city of Sendai. Tremors are common throughout Japan, and this one was near the Japan Trench, where the Pacific plate, the speediest of the earth’s major slabs of crust, dives beneath the islands of Japan in what’s called a subduction zone. There was a major tremor, magnitude 7.9, just two days ago — what now looks like a foreshock. But although this is a seismic zone, part of the so-called Ring of Fire that lines much of the Pacific, until recently it wasn’t considered one of Japan’s most vulnerable areas. Japan a leader in quakeproof structures. Huge rubber shock absorbers, walls that slide and Teflon foundation pads that isolate buildings from the ground all help explain why medium- and highrise structures in Japan remain standing in the wake of the country’s largest earthquake on record, construction experts said Friday.
The location of the earthquake, 130 kilometres offshore, might also explain why most of the structural damage reported appears to be from the tsunami that followed the quake rather than the shaking itself. Since the devastating Kobe quake in 1995, Japan has become a world leader in engineering new structures and retrofitting old ones to withstand violent shaking. “The Japanese are at the forefront of seismic technology,” said Eduardo Kausel, professor of civil and environmental engineering at MIT.
“All modern structures have been designed for earthquakes.” The omnipresent threat of large quakes has turned shakeproof innovations into selling points for new high-rises, drawing higher rents, Hamburger added. Destructive Power of Tsunami Waves. Scientists unlock tsunami secrets. Limits of Human Foresight against natural disasters. NTV Japan, via Associated Press UNAVOIDABLE A tsunami wave, as it heads to shore in the area of Natori City, Japan. Japan is a rich, high-tech nation with much rough experience of seismic rumblings: those factors have led it to plan, and plan well, for disaster, with billions spent over the years on developing and deploying technologies to limit the damage from temblors and tsunamis.
Those steps almost certainly kept the death count lower than it might otherwise be — especially in comparison with the multitudes lost in recent earthquakes in China and Haiti. Last Friday, however, showed the limits of what even the best preparation can do. “I’m still in shock,” said Ivan G. “This is really the best analogue we have for the United States,” he said, and “I’m just flabbergasted by the amount of damage we’re seeing.” Mr. “Steps are being taken, but there’s a lot of dams, there’s a lot of fixing that needs to be done,” Mr. Dr. And yet there are few issues as important. Mr. Japan’s Seawalls Were Little Security Against Tsunami. US Disaster Preparedness Questioned. While Japan struggles to respond to multiple catastrophes stemming from last week’s earthquake and tsunami, America’s disaster preparedness leaves room for improvement.
It has been more than five years since Hurricane Katrina devastated America’s Gulf Coast and exposed significant shortcomings in the nation’s ability to respond to a major disaster. Since then, FEMA, the Federal Emergency Management Agency, has improved its operations and preparedness, according to former Homeland Security Inspector General Richard Skinner. But deficiencies remain, according to a report Skinner wrote last year before retiring and presented to the Senate Thursday.
"We have made tremendous strides over the last four years since Hurricane Katrina. Skinner said FEMA is moving in the right direction in upgrading its capabilities, but doing so at what he termed a "snail’s pace. " "Japan has been considered the gold standard of earthquake preparedness because they have had repeated experience with earthquakes. Japan's Tsunami: How It Happened. Tsunamis, such as the one generated by the magnitude 8.9-magnitude earthquake that struck Japan today (March 11), are often generated by massive ruptures beneath the Earth’s surface underneath the ocean floor.
When the earthquake ruptures along a fault line, the surface around that fault is pushed up and then dropped back down. (Not all undersea quakes generate tsunamis, as some occur so deep in the Earth's crust that they won't cause this push.) That movement displaces the entire water column above that chunk of the surface. "This is the most common way to generate a tsunami," said Aggeliki Barberopoulou of the University of Southern California's Tsunami Research Center, who is monitoring the current tsunami as it affects California. The earthquake near the east coast of Honshu, Japan, ruptured at 05:46 GMT (2:46 p.m. local time), immediately putting in motion the tsunami.
Wave begins The waves hit the eastern coast of Japan about 1.5 hours after the quake, Barberopoulou said. The Science of Japan’s EQ. 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.
The Kobe tragedy, says The Telegraph‘s Peter Foster, compelled Japanese officials to tighten building regulations for residential offices and transportation infrastructure. Why Couldn’t Geologists Predict It? Some people may be asking themselves why geologists couldn’t predict today’s earthquake: Didn’t the smaller shocks earlier in the week give some inkling of Friday’s crusher? How the Tsunami Formed And it didn’t stop at the town: It plowed right through airports as well.
Science of the EQ. Developments in the wake of Japan's triple disasters: earthquake, tsunami, nuclear. The US Geological Survey upgraded Japan's 11 March earthquake today to 9.0 from 8.9. Based on Japan's huge network of 1,200 GPS monitoring stations, the quake shifted the country's coastline some 4 meters / 13 feet to the east, and knocked Earth of its axis by 16.5 centimeters / 6.5 inches, shortening Earth's days by about 1.8 millionths of a second.
The BBC reports that geographical shift will require that GPS-based driving maps be updated, and nautical charts, too, since water depths have been changed. Furthermore, much of the flooded coastline appears to have subsided permanently—or as permanently as anything ever is on this restless planet—and will not be dry land again anytime in the near future. Credit: NASA Earth Observatory image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S. Credit: US Navy, via Wikimedia Commons. Credit: NASA/GSFC/LaRC/JPL, MISR Team. Japan EQ: 5h strongest on record. Fast Facts about the Japan EQ and Tsunami. Japanese EQ reminds us how Building Codes save lives. Zero Tokyo Buildings Collapsed Thanks to Stringent Building Codes. Infographic Japan's EQ. Japan's Explosive Geology. How Japan’s Building Codes Prevented Casualties. Japan’s strong building codes keep millions safe. Japan's strict building code may have helped save lives.
Japanese Tsunami's Effects Will Change How and Where Future Nuclear Power Plants are Built. Size of Japan EQ surprised even scientists. Why Japan's EQ was so strong.