Tag Archive: Earthquake


The Earthquake and Tsunami

The magnitude 8.9-9.0 Sendai earthquake was one of a handful of such powerful megathrust earthquakes to occur in recorded history. Its epicenter was 130 km (81mi) off the east coast of Miyagi Prefecture and it took place at a depth of 24.4 km (15.2 mi). The huge earthquake shook buildings on land while sending a 6.9-10 m (23-33 ft) tsunami toward the northeastern coast of Japan. It swept inland as far as 10 km (6 mi), causing immense destruction to the area, which can be see through satellite photos from the New York Times.

British Channel 4 Footage from the tsunami in Japan (Channel 4 News, via Real News)

The waves excavated homes and factories and have dealt a second blow as two nuclear power plants were so heavily damaged by the earthquake that they may be in partial meltdown. More than 10,000 people are dead, hundreds of thousands are homeless, 4.4 million have been left without electricity and 1.4 million do not have water. If you would like to help, click here for a list of organizations that are assisting with the recovery efforts.

Nuclear Power

Fission of Uranium 235 (theblogprof)

All current nuclear power plants are fission plants, involving the splitting of atomic nuclei. In most powerplants, this occurs when a neutron collides with a Uranium-235 (235U) nucleus and is absorbed by it. The 235U was relatively stable, but 236U is unstable and it will break into five pieces, a Krypton-92 (92Kr) nucleus, a Barium-141 (141Ba) nucleus, and three free neutrons. In a bar of Uranium, these free neutrons can collide with other Uranium atoms, which in turn give off more neutrons, and so on. This is what we call a chain reaction.

In addition to the neutrons, heat is given off as well side-reaction chains that generate a few electrons and some radiation. The heat is used to create steam, which drives a turbine that creates electricity. Electrons that escape the reactor core into a surrounding water tank can create a bluish glow, called Cherenkov Radiation, as they pass through water.

Cherenkov radiation creates the blue glow in a water-cooled nuclear fission reactor (WP Clip Art)

Despite the fact that an Uranium is a very heavy element, its nucleus is still rather small compared to the size of the atom itself (including the electron shells). That means that even a heavy rod of Uranium contains mostly empty space at the atomic level. As a result, the free neutrons do not necessarily hit the Uranium nuclei sitting right next door. They can rather travel a good distance through the material before the are absorbed by another nucleus. If the bar of Uranium is too small, then too many neutrons will escape before they can collide with other atoms and in that case, there will be very few nuclear reactions.

This can be remedied by putting a enough of fissile Uranium together to ensure that neutrons will be absorbed by the 235U, but one must be rather careful about it. If too much Uranium is placed together in a small, confined place, there could be a runaway reaction that releases a good deal of all of the energy that is stored in the atomic nuclei in a very short time (read: boom). This video gives a good demonstration of the chain reaction process.

A simulated nuclear reaction using mousetraps and pingpong balls (paulnord, YouTube)

Editor’s note: I once put together a similar demonstration with 1,000 mousetraps. At one point, we reached 500 only to have a ping pong ball go off. Not good. I also remember being a bit gun shy around snapping sounds after that. My fingers were very sore at the end of the setup.

To avoid a runaway reaction, most nuclear power plants use a combination of Uranium and Carbon rods to moderate the reactions rate. The Carbon rods essentially absorb the neutrons before they can reach a Uranium atom. With fewer neutrons reaching the Uranium, the reaction rate slows. If higher rates are required, the power plant simply removes some of the carbon rods to increase the number of neutrons that generate new reactions.

The Fukushima-I (Daiichi) plant runs on a variant of this process, which incorporates Uranium and Plutonium Oxide fuels. The same general principles apply, though the specific isotopes involved in the reactions are somewhat different.

In any case, the heat generated by the reactor core is used to boil water. Each of the plants have variations on this theme, but the general idea is depicted here. Water can be heated to very high temperatures if it is kept under pressure, these plants carry superheated water into a seperate chamber to create steam. As the steam is generated, the formerly superheated water cools, and is recirculated to the reactor core. This has the effect of carrying heat away from the reactor core and regulating the reaction rate (which increases as it heats up, causing more heating). If the temperatures of the reactor were to rise to high, the Uranium rods could melt and create a molten puddle of Uranium at the bottom of the chamber. This is a meltdown and carbon rods would no longer be able to regulate the reactions if a meltdown were to take place. In a sense, there is no “off switch” for a nuclear reactor, especially one that has melted down.

Status of the Power Plants

The events in Japan are taking place quite rapidly, and from what I can see, no one is completely certain regarding whether the plants have melted down.

    Fukushima-I (Daiichi):

Three of six reactors (1,2 and 3) at Daiichi were operating and went into automatic shutdown prior to the tsunami. However, the emergency generators used to cool the plant stopped in unit 1 after the tsunami. Units 2 and 3 were still alright by this point. Temperatures began to rise and steam was vented to release pressure on the containment structure. A hydrogen explosion, caused by a buildup of the gas, occurred and damaged the exterior of the building, though the reactor core containment structure seems alright. Seawater was pumped in to cool the cores.

Fukushima-I before and after the Hydrogen explosion (NHK, via Wikipedia)

By March 13, reactor 3 began having trouble and venting was necessary. The core was not completely covered by water, and there may have been some damage to the core. Nearly 200,000 people were evacuated from the area, and 22 residents have shown signs of radiation sickness. On March 14, the Unit 3 building was destroyed by a hydrogen explosion.

    Fukushima-II (Daini):

All four units of this plant were shut down automatically, but Units 1,2 and 4 were damaged by the tsunami and an evacuation was ordered due to possible radioactive contamination. By March 12, the temperature of the reactors had reached 100oC. No pressure release has yet occurred, however. Residence have been evacuated to a distance of 20 km from the plant.

    Onagawa:

A fire began in the turbine section of the plant after the earthquake. On March 13, radiation levels reached 21μSv/hour, causing a state of emergency to be declared – the International Atomic Energy Agency’s lowest emergency level. After a few minutes, the radiation levels dropped by half and have now returned to background levels.

Japanese authorities believe that the elevated radiation levels at Onagawa were due to the Fukushima I (some 60 km away) accident rather than from Onagawa itself. The radiation levels at Onagawa were not incredibly high, but their increase was cause for alarm. It is not known, however, how high a dose of radiation that the 22 people near Fukushima I had received. Only time will tell. 1,500 others are being tested for radiation exposure as a precaution.

So far, radiation levels are not expected to rise very much in Alaska and Hawaii.

Officials are saying that there is a 70% chance of a magnitude 7 aftershock by Monday. The situation is already a long way from being finished. A large earthquake could make things worse. At the moment, there are still reactors threatening to require venting. Venting is fairly safe, provided that the fuel rods are intact, however it seems there has been at least one partial meltdown. That means that vented gas may become more radioactive as time goes on. In addition, the sea water that is being used in desperation to keep the reactors cool will eventually corrode the metal containment chamber. The stakes are incredibly high – whether a significant fraction of the northern part of the densely populated country will be inhabitable.

Hopefully the earthquake will not arrive. The last thing anyone needs is another challenge at the moment. Good luck to everyone involved in bringing the reactors under control. Stay safe.

Here is that link again if you would like to help out.

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I have found a few websites that you can donate to if you would like to help out with the situation in Japan. Here is a list of a few organizations that are currently involved with the efforts to assist people who have been affected by the earthquakes and tsunami from this weekend.

Tzu Chi: A Buddhist volunteer organization with 10 million volunteers in 50 countries (about 120,000 in the U.S.) and only a small support staff. All of your donations go to victims without proselytization.

Doctors Without Borders: A humanitarian organization in which doctors provide impartial medical assistance in places stricken by war or natural disasters.

The Red Cross: A famous emergency response organization. It provides neutral humanitarian care to victims of wars and natural disasters.

Global Giving: An organization designed to help people give toward charities they care about to make positive change in the world.

More info can also be found at the Huffington Post.

Artist depiction of Michele Bachmann's inner thoughts (yo2boy)

US Federal Budget

Fear not! Michele Bachmann know’s who to turn to to solve the Federal Budget Deficit! Sure, we all know that the Tax Code is a Weapon of Mass Destruction, but who better to handle WMDs than Glenn Beck? Do not get all of the apocalypse porn get to you and do not let the fact that he can not tell the difference between a socialist and a fascist bother you, but he is full of … it.

Returning to the real world, the US Budget is a big point of contention, with Republicans gearing up to defund everything that makes America a modern nation. Rachel Maddow has a great piece on how the GOP is defunding the Corporation for Public Broadcasting but how it wants to give more money ($40 billion) to big oil. Meanwhile, Representative Anthony Weiner (D-NY) asks the GOP why they want to get rid of government health care for the middle class, but they do not want to get rid of their own government health care. Current Office of Management and Budget (OMB) estimates suggest that the Tea Party/Republican proposal to cut $100 billion in discretionary spending would kill nearly 1 million jobs and cause the second Republican-induced recession in three years.

News from Abroad

A number of people are dead after a shallow 6.3-magnitude earthquake strikes Christchurch, New Zealand. The earthquake was followed by magnitude 5.5 and 5.6 aftershocks as well.

Fired upon in a sneak attack Thursday evening, protestors swelled in numbers Friday as they took back Pearl Square in Manama, Bahrain. They had been calling for a constitutional monarchy and now they are calling for the king’s head. After the king told hospitals not to treat demonstrators, Britain and France have stopped exporting crowd control weapons to Bahrain, but will the US do the same in the nation where it holds a huge naval base?

While students protest in Algiers, Trade Unions continue to protest in the streets in Tunisia. Workers are also calling for higher wages in Egypt, though the mention of the labor movements that brought down dictatorships in these two countries is simply called a “democracy” movement by the corporate American press.
Cracks appear in the Gadhafi regime as the military attacks jets to attack the crowds. Violence against the nonviolent protests has been fruitless throughout the Middle East and Libya is no different: Demonstrators now occupy several major cities, including the second largest city Banghazi, despite reports of heavy casualties there and in Tripoli. Two Libyan military jets also landed in Malta seeking asylum rather than fire on civilians.

In Pakistan, an American arrested for murder in Lahore is a CIA covert agent. Relations with Pakistan are already tense due to numerous civilian deaths after a large number of American drone attacks on its supposed ally. This also comes just a day after American airstrikes in Afghanistan kill 64 civilians, according to the Kunar provicial governor.

Labor protests in America – On Wisconsin!

Protests continue strong in Wisconsin as Egyptians purchase pizzas for state employees over the internet, saying ‘We Stand With You As You Stood With Us’ in a beautiful statement of solidarity. The protests in Madison met for the eight day as another round of mammoth protests are scheduled for Tuesday across the country.

Tea Party New Jersey Governor Christie faces the possibility of protests as he plans to force staff to pay more toward benefits. Labor unions have already marched in Trenton in solidarity with demonstrators in Wisconsin. Angry union workers filled the Statehouse in Indianapolis as Tea Partiers in a legislative committee approved a measure to eliminate collective bargaining rights for state employees, approving a Chamber of Commerce-supported “Right to Work” bill. The Tea Party Governor of Michigan will not push for a similar measure, saying he won’t “pick fights” with unions by following the same path as Wisconsin’s Walker. In nearby Illinois, workers from Chicago are joining the Madison protests. More workers joined protests across the state of Nevada in solidarity with the Wisconsin state employees, while hundreds gathered in Helena, MT to argue against state budget cuts, crazy legislation and for solidarity with Wisconsin.

More protests are scheduled around the country Tuesday, including:

Little Rock, Arkansas
Phoenix, Arizona
Palmdale, California
Sacramento, California
Denver, Colorado
Des Moines, Iowa
Annapolis, Maryland
Boston, Massachusetts
Springfield, Massachusetts
Saint Paul, Minnesota
Santa Fe, New Mexico
New York, New York
Columbus, Ohio
Providence, Rhode Island
Montpelier, Vermont
Madison, Wisconsin