miércoles, 23 de marzo de 2011

Earthquake and Tsunami in Japan

Earthquake and Tsunami in Japan

by ArchitectureWeek

As the world knows, a huge earthquake of magnitude 9.0 and devastating tsunami hit Japan on Friday afternoon, March 11, 2011, with impacts centering in the vicinity of Sendai.

Update — 04:10 on Tuesday, March 22, 2011 in Tokyo — Monday, 19:10 GMT — Monday, 2011.0321.12:10 PDT

Periodic updates for this story are posted here, with additional interim updates posted on the cover page.

Preliminary estimates of the death toll surpass 10,000 (Reuters). More than eight thousand deaths are confirmed across Japan as of Sunday, 3/20/2011, and a larger number of people are still missing, with the total still rising.

"Many areas of the town are simply gone" in Sendai (CNN) and other communities. Major tsunami damage is reported for a length of 500 km (over 300 miles) along the northeastern Japan coastline. To date, though losses due directly to earthquake shaking appear to be significant, the losses from tsunami inundation appear to be very much greater.

Communications are largely down and roads are blocked by debris in much of the disaster area. Water, food, and transportation fuel are in short supply. Nearly all train lines remain shut down in the broad disaster area, and all Shinkansen service northeast from Tokyo was suspended. Japan Rail announced limited national service on Monday.

More than 440,000 people were stated to be in some 2,400 evacuation shelters (NHK) across northeastern Japan, and the actual number may be higher. Nights are cold and heating is in short supply in shelters. Rain and snow has started in the disaster area

People were also still waiting for rescue outdoors a week into the disaster, and in many isolated locations, as many smaller communities and parts of larger communities remained isolated by flooding, debris, and road damage. Thirty-two bridges were currently reported damaged, and 66 landslides were reported (NHK). Widespread debris even hampered helicopter rescues. As of Monday morning, March 14, 2011, 24,000 residents were identified as stranded in 80 isolated locations (NHK).


Wednesday night in Japan represented the passage of more than five days since the disaster started on Friday afternoon. The temperature overnight has been around freezing in the Sendai area. Rain and snow have been falling in Fukushima prefecture.

Emergency shelters were reported to be running low on water, food, and fuel as of Monday night. Resupply efforts to the millions in the 500-kilometer-long (300-mile-)disaster area appear to be fractional so far. Rescue efforts continue. Bodies have washed ashore in many areas.

Ongoing Triple Nuclear Accident

Partial reactor core meltdowns have now occurred at three struggling nuclear reactors at a power plant in Japan north of Tokyo (NY Times). After an explosion at reactor #2 at around 6am Tokyo time on Tuesday morning, radiation levels measured outside at the plant increased greatly, to 8200 microsieverts (NHK), or more than eight times the allowable annual exposure. Radiation levels have fluctuated since and information is skimpy.

All three reactor units at the Fukushima Daiichi Power Plant (Fukushima Number One Power Plant) have experienced serious explosions, explosions of vented hydrogen on Saturday (reactor #1) and on Monday (reactor #3), which destroyed the reactor containment buildings, but not the reactor containment vessels, and a less-well explained explosion on Tuesday morning at 6:10am at reactor #2, the latest reactor unit to go significantly out of control, with 2.7 meters of control rod exposure above coolant. An extremely dangerous level of cooling problems is now reported for all three reactors. At reactor #2, Tokyo Electric Power Company (TEPCO) has said the inner containment vessel system may have ruptured.

Above-normal releases of radiation and radioactive material are continuing from all three permanently damaged reactors — #1, #2, and #3 — at Fukushima Daiichi. With containment buildings gone around two of the three badly damaged reactors, fuel cores damaged, and emergency cooling continuing with a "boil off" method, essentially unpreventable radioactive releases are likely to continue for weeks. In addition, cooling problems and fire at a large spent fuel storage pool at reactor #4 have apparently led to increased radiation releases there.

More detailed coverage of the nuclear plant disaster associated with the earthquake and tsunami is online at Beyond Three Mile Island.

Widespread Shortage of Electric Power

In addition to several crippled nuclear power plants which are now permanent liabilities, conventional thermal power plants have been impacted by the earthquake and tsunami and are also offline.

The utility company Tokyo Electric Power Company (Tepco) called for conservation efforts and announced rolling power blackouts starting Monday morning, with available generating capacity at 31 million kilowatts, compared to typical demand of 41 million kilowatts.

Planned outages in the Tepco service area, including Tokyo except its central area, and the prefectures of Chiba, Gunma, Ibaraki, Kanagawa, Tochigi, Saitama, Yamanashi and part of Shizuoka, are currently expected to continue until the end of April. Ongoing announcements are providing changing details as the situation evolves (NHK).

Intentional power outages started on Monday, and affected four prefectures during Monday evening. The rotating outages are continuing.

Large Tsunami Overwhelmed Extensive Defenses

One of the tsunami waves was measured at 7.3 meters (24 feet) (NHK), and actual peak heights were probably greater. "Sendai residents said the water reached the treetops as it swept into the town" (CNN). Given the scale of the waves, protective breakwaters built along the coast failed to provide effective protection, including the 10-meter (33-foot) seawall at Taro in Miyako City, which was heavily overtopped. Tsunami damage is reported as far as 10 kilometers (about six miles) inland, and can be seen more than 5 kilometers (3.1 miles) from normal high water right in Sendai.

Some people were swept away after retreating to evacuation locations that were then inundated. One woman, interviewed on NHK on Sunday, described with tears the horrible experience of being torn by the flood from the third story of a building, where she had evacuated with her daughter, who was then torn from her grip. The woman was grabbed by other survivors as she swept by, and pulled from the flood waters, but her daughter disappeared.

The quake magnitude has been upgraded to 9.0 by Japanese authorities (NHK). Aftershocks have included several quakes of magnitude 7. Athorities have warned that large aftershocks have the potential to trigger additional tsunamis.

Geologists at the University of Tokyo have estimated that ocean floor uplifted in the main subduction zone earthquake by several meters, with an uplift area of 200 by 500 km (125 by 310 miles).

An estimate by the Earthquake Research Committee of Japan is that the tectonic plate including Japan shifted eastward by about 20 meters (66 feet). Other estimates suggest a few meters of horizontal displacement. The researchers also say the quake caused areas from Iwate to Fukushima prefectures to sink up to 75cm (29.5 in.). (NHK)

Sendai Mediatheque

At the time of the earthquake, the ArchitectureWeek cover story featured the Sendai Mediatheque and an interview with its architect, Toyo Ito.

This video posted at YouTube, taken inside the Sendai Mediatheque during three minutes of the intense earthquake shaking, shows what it was like to ride out the massive quake in a well-engineered modern structure:

Impacts Still Emerging

Heart-wrenching and horrifying eyewitness disaster videos are continuing to be released as more survivors make contact.

On Monday evening in Japan, there are reports of food stores closed and shelves empty even in Tokyo. A mall in Tokyo is reported closed to save electricity. Some gasoline shortages are being reported in the Tokyo area.

Toyota announced that 12 auto plants would be closed on Monday, and Toyota plants in Japan remain closed. Honda announced plants closures due to parts shortages. Sony and other major Japanese manufacturers have also closed factories.

The Bank of Japan provided massive support to Japanese banks and financial markets during the business day on Monday.

The Japanese government reported recently that at least 6,300 buildings and houses collapsed in the quake or were washed away by the tsunami, and at least 76,000 buildings were damaged (NHK). These counts will continue to rise.

Behind the huge numbers are a million poignant, devastating details. In Ishinomaki, Miyagi prefecture, a large tour bus sits on top of a three-story building. A house sits where it floated on top of a two-story elementary school. On Friday morning, the wide plain of debris that now stretches between these two buildings had been close-packed with many rows of houses. (NHK video)

Overall damage assessment is still in its early stages, with rescue efforts the priority. Specific architectural assessment is understandably skimpy at this stage of the events. Evidence of structural damage and building collapse due to shaking and subsidence can be seen in media photographs and video.

According to the Tohuku Electric Power Company, about 850,000 households in the north are still without electricity in near-freezing weather. The BBC relays a government statement that at least 1.5 million households lack running water.

The U.S. Pentagon announced that eight U.S. Navy ships are now assisting off the coast of Japan, including the aircraft carrier Ronald Reagan, and five more U.S. Navy ships are en route.

After the incident Monday involving radioactive contamination of three U.S. Navy helicopter crews, the US Department of Defense tweeted, "Despite precautionary repositioning of ships near Sendai, we remain committed to the mission to #HelpJapan."

Satellite imagery of the disaster area is now available via NASA and Google.

No hay comentarios:

Publicar un comentario