The truth behind the fearless Nankai earthquake prediction numbers

This is the first in a series of survey reports from Chunichi Shimbun on how to manipulate Nankai Trough earthquake probability figures for a report by a government experts panel released in February 2018.

That was a few days before February 9, 2018, when the Seismological Research Committee, the government’s expert panel, announced that it had revised its forecast for a major earthquake in Nankai, off the coast of Japan’s Pacific, in the 30 years from about 70 percent to between 70 And 80 percent.

I got information about the revised number from a source and I started out in the corners of the story like whether disaster prevention measures were enough and the amount of damage a huge earthquake could cause in the Tokai area.

First, for an expert comment on the review, I called Takeshi Sagiya, an seismologist and professor at the University of Nagoya, expecting to hear his alarming voice on disaster preparedness. But the comment he made was unexpected.

He said, “I personally think it is very misleading.”

“If the government provides a figure of 80 percent, people believe that the next earthquake will be the Nankai earthquake, and disaster prevention measures will focus on this particular earthquake,” Sagia said. “It’s okay if the actual risk level is the same as the expected number. But this is not the issue. This is a complete misunderstanding. The numbers only fuel the sense of crisis. I think this is a problem.”

Numbers inflated

misunderstanding? problem? I was confused by the comments. Then Sagiya said something more shocking.

“The probability of the Nankai Basin earthquake is high because the Nankai Basin earthquake is receiving special treatment,” he said. “The numbers are exaggerated because of the special treatment and ulterior motives.”

These unexpected words – inflation, special treatment and ulterior motives – puzzled me more and prompted me to investigate further.

“A different method was used to calculate predictions only for the Nankai earthquake. We should not call this science. Seismologists said that seismologists consider them untrustworthy. If they use the same method used in other regions, the number will drop to about 20 percent. Many seismologists say the same method should be used (for the Nankai Trough earthquake), but people in charge of disaster prevention claim that the number should not be lowered at this point.

Earthquake forecasts were first presented by seismologists in a subcommittee on ocean trench earthquakes for approval by the Seismological Research Committee, which is part of the government headquarters to promote seismic research headed by the Minister of Education, Culture, Sports, Science and Technology.

During the subcommittee meetings in 2012, seismologists called for the need to use consistent calculation methods to ensure the reliability of forecasts. The 70 percent reduction in the Nankai earthquake was to be cut significantly. But the proposal was said to have faced stiff opposition.

It was difficult for me to understand the mechanisms of the two different methods used to calculate earthquake probabilities by simply listening to Sagiya’s interpretations over the phone.

But it was clear why the estimate for only the Nankai earthquake was exceptionally high – a different computational method was applied that seismologists believed was not reliable. Moreover, there was a hidden agenda explaining why some people were reluctant to use a coherent method nationwide.

Questionable factors

“Do you know how to calculate the probability of the Nankai earthquake?” Sajia said, “It is based on the disturbances that occurred at (Moroto) port, northwest of Cape Moroto in Kochi Prefecture, which were recorded three times between 1707 and 1945.” But how do you get On the (probability ratio) only how much did the Earth rise in the past? The method is full of questionable factors. I wonder how many researchers think the number is really reliable. But that has never changed. “

Before calling Sagiya, I called the main office of Chunichi Shimbun and an official editor said it would be better not to publish the news because readers would overreact to the number. After talking to Sagiya, I thought the editor made the right call.

A short story was published on the day of the announcement, saying that the government’s Seismic Committee “revised slightly up from last year the probability that an 8 to 9 earthquake in Nankai Basin would hit within 30 years to between 70 and 80 percent.”

I was feeling uncomfortable, thinking that there should be something else in the story, I remembered Sagiya’s comments before I switched off the phone: “I’m sure the discussions that took place at the sub-committee meetings are all recorded in minutes.”

She submitted an application to disclose the information to the Ministry of Education, and after about a month, she obtained the records, which revealed many surprising comments that were never revealed.

Quite surprising

Surprisingly, the record showed that the panel’s experts strongly opposed the methods used to calculate the probability of the Nankai True earthquake.

The Sub-Committee on Ocean Trench Earthquakes includes prominent seismologists listed as members and is charged with assessing the latest earthquake potential across the country.

Revised sections of the minutes of the government’s Seismic Research Committee meeting on the Nankai Basin earthquake. | Shonishi Shimon

Minutes of the subcommittee meetings held between 2012 and 2013 – obtained by Chunichi Shimbun – showed that although the exact names of those who made the observations were withheld, almost all members expressed doubts about the method of calculating the opportunity of Nankai Pelvic Earthquake that occurred within The next 30 years.

As of 2012, the likelihood of such an earthquake was said to be between 60 and 70 percent.

One member said: “If we calculate the probability now by using the method that we use the entire time, we will reach 70 or 80 percent for the next thirty years. But we must mention somewhere that the number could be 20 percent if we use a different method.”

It is quite surprising to see that there were eight years ago discussions about the reliability of the numbers. So why did they release the numbers?

Not valid scientifically

Another member questioned the method that leads to high probabilities, saying: “If you allow me to make a scientific argument, I undoubtedly think it is not correct to preserve (the previous method). There are opinions that the predictable model of time (used in the method) Not valid at least on this subcommittee, so I am not convinced to reveal the number. “

The “anticipated time model” apparently refers to a special method used only to calculate the probability of the Nankai Basin earthquake – which Sagia described as a method that allows numbers to be amplified and specially treated.

The Earthquake Research Committee announced in May 2013 that the chance of an earthquake of 8 or more magnitude in the Nankai Basin within 30 years was between 60 and 70 percent. However, it appears that no explanations have been provided on the calculation method, let alone the time prediction model.

The press release issued at the time of 2013’s announcement No. 20 was not mentioned at all in its summary referred to as the “main text”. Despite all the heated debate over the issue, she is buried in the last part of the massive document, as if to make it intentionally unclear.

The method described in the record is applied as a basis for 20 percent to calculate the probabilities of all other earthquakes expected in Japan. Its purpose is to determine the probability by calculating the average frequency of occurrence from previous earthquake data.

However, earthquakes in the Nankai Basin have varied greatly in the past, with the region struck once during a few decades at times and every centuries at other times. From the point of view of human life, the “within 30 years” period used to calculate the probability is long but short in terms of seismic cycles. Therefore, it is relatively normal for earthquake probabilities to be low.

Moreover, by reading the record, it became clear that seismologists were skeptical of calculating probabilities in the first place.

The minutes included many comments from members that showed negative reactions to the presentation of possibilities.

“It has different problems,” “That doesn’t mean much,” “I have no idea why we offer this,” “We shouldn’t provide this,” “We can’t do it, whatever it is.” And so on.

The effect makes a difference

A member’s comment said it all.

“The probability figure has a huge impact. So it is quite understandable that people want to rely on it, as well as the possibility of precipitation, which is familiar and easy to understand. But it is difficult to take advantage of the possibilities of earthquakes, because earthquakes do not happen often.”

Even the forecast of precipitation was not highly probable, so real-time data on changes in the atmosphere became available. Why did this predictable time model predict a probability of up to 80 percent of the Nankai earthquake? Why did the annual probability figure continue to rise like the forecast for precipitation in the coming hours?

All answers were in minutes.

Keiichi Ozawa is the reporter of Chunichi Shimbun who covered nuclear energy and earthquakes after the earthquake caused by the earthquake in the Fukushima No. 1 nuclear power plant in March 2011. Ozawa received the Science Journalist Award presented by the Japan Association for Science and Technology Journalists in June, for this series published Between October and December 2019.

.

What Are The Main Benefits Of Comparing Car Insurance Quotes Online

LOS ANGELES, CA / ACCESSWIRE / June 24, 2020, / Compare-autoinsurance.Org has launched a new blog post that presents the main benefits of comparing multiple car insurance quotes. For more info and free online quotes, please visit https://compare-autoinsurance.Org/the-advantages-of-comparing-prices-with-car-insurance-quotes-online/ The modern society has numerous technological advantages. One important advantage is the speed at which information is sent and received. With the help of the internet, the shopping habits of many persons have drastically changed. The car insurance industry hasn't remained untouched by these changes. On the internet, drivers can compare insurance prices and find out which sellers have the best offers. View photos The advantages of comparing online car insurance quotes are the following: Online quotes can be obtained from anywhere and at any time. Unlike physical insurance agencies, websites don't have a specific schedule and they are available at any time. Drivers that have busy working schedules, can compare quotes from anywhere and at any time, even at midnight. Multiple choices. Almost all insurance providers, no matter if they are well-known brands or just local insurers, have an online presence. Online quotes will allow policyholders the chance to discover multiple insurance companies and check their prices. Drivers are no longer required to get quotes from just a few known insurance companies. Also, local and regional insurers can provide lower insurance rates for the same services. Accurate insurance estimates. Online quotes can only be accurate if the customers provide accurate and real info about their car models and driving history. Lying about past driving incidents can make the price estimates to be lower, but when dealing with an insurance company lying to them is useless. Usually, insurance companies will do research about a potential customer before granting him coverage. Online quotes can be sorted easily. Although drivers are recommended to not choose a policy just based on its price, drivers can easily sort quotes by insurance price. Using brokerage websites will allow drivers to get quotes from multiple insurers, thus making the comparison faster and easier. For additional info, money-saving tips, and free car insurance quotes, visit https://compare-autoinsurance.Org/ Compare-autoinsurance.Org is an online provider of life, home, health, and auto insurance quotes. This website is unique because it does not simply stick to one kind of insurance provider, but brings the clients the best deals from many different online insurance carriers. In this way, clients have access to offers from multiple carriers all in one place: this website. On this site, customers have access to quotes for insurance plans from various agencies, such as local or nationwide agencies, brand names insurance companies, etc. "Online quotes can easily help drivers obtain better car insurance deals. All they have to do is to complete an online form with accurate and real info, then compare prices", said Russell Rabichev, Marketing Director of Internet Marketing Company. CONTACT: Company Name: Internet Marketing CompanyPerson for contact Name: Gurgu CPhone Number: (818) 359-3898Email: [email protected]: https://compare-autoinsurance.Org/ SOURCE: Compare-autoinsurance.Org View source version on accesswire.Com:https://www.Accesswire.Com/595055/What-Are-The-Main-Benefits-Of-Comparing-Car-Insurance-Quotes-Online View photos