専門せんもん家か “今回こんかいの津波つなみは後ごから来くる津波つなみが大おおきく 注意ちゅういが必要ひつよう”

Regarding the characteristics of this tsunami, Professor Fumihiko Imamura from the International Research Institute of Disaster Science at Tohoku University, who is well-versed in tsunami mechanisms, said, There have been major earthquakes in the Kamchatka Peninsula in the past, with the largest one occurring in 1952, and this one happened on a similar scale.

At that time, a 3-meter tsunami also hit Japan.

He pointed out that there is a risk that this time will be on a similar scale as well.

In addition, regarding the characteristics of tsunamis that occur off the coast of the Kamchatka Peninsula, Professor Imamura said, I think the time it takes for the tsunami to arrive will be as predicted, but the waves that come afterward may become considerably larger, and the largest wave may arrive later.

He urged people to keep updating the latest information from sources such as the Japan Meteorological Agency, as there is a possibility that the effects of the tsunami may continue for a longer period of time.

Professor Imamuras Explanation as of 3:30 p.m.: We spoke with Professor Fumihiko Imamura of the International Research Institute of Disaster Science at Tohoku University, who is well-versed in tsunami mechanisms.

Q

In Kuji City, Iwate Prefecture, there was footage of the water level rising and falling a little after 1 p.m. Based on this footage, what can we say about the situation?

A

I think this reflects the characteristics of this distant tsunami.

Looking at the video and the tide records, the time of the tsunamis ebb and flow is about one hour.

You can see that it slowly rises and falls within this range, repeating this pattern.

We suspect that, rather than a conventional wave-like or wall-like tsunami, it is a situation where the water rises slowly but the current is strong.

Q

Tsunamis have been observed in various areas, but how are the other characteristics being analyzed?

A

Currently, waves 1 through 4 are being observed, and looking at these waves, each one is roughly two to three times larger than the previous one.

I think the tsunami will continue to ebb and flow, but there are still concerns about it becoming amplified.

I think the maximum width will probably be the one that comes out from now on.

Q

At Kuji Port in Iwate Prefecture, it was reported to be 1 meter 30 centimeters, but is it possible that the height could still increase?

A

Thats right.

In addition, the tide level is currently heading toward a higher-than-usual high tide, so with that trend as well, there is a possibility that the sea level will become quite high.

In addition, there is a risk that the height will continue to increase in various areas.

Q

At the Japan Meteorological Agencys press conference, they mentioned that the tsunami is expected to last for about a day or longer. Should we assume that tsunamis generally continue for such a long period of time?

A

I think that, like this time, a large earthquake is affecting a wide area around the Pacific Rim.

Tsunamis dont just come directly from various directions; they also get reflected from other areas or wrap around, so their effects keep increasing.

It will probably take more than half a day, maybe even a whole day.

In the case of the Great East Japan Earthquake, we couldnt lift the advisory for a day and a half.

Q

This time, you mentioned that the tsunami is characterized by having a relatively long period. In such a case, what kind of damage should we be concerned about?

A

In this case, since the current is strong, there are concerns that ships and aquaculture rafts may be swept away, or that drifting debris may cause damage.

Also, it will make it easier for fish to swim upstream in the river.

Q

At first glance, it may look like the water level is quietly rising, but does that mean this current is actually very strong?

A

So-called fresh water, which is extremely heavy, moves within a certain flow, so from what weve seen, the destructive power it has is beyond what we could imagine.

Q

As I observe the changes in the data so far, I still dont see any signs of attenuation.

Should I assume that this will continue for a while longer?

A

Thats right.

Some parts of the fifth wave are already being observed from the fourth wave now.

Since there is no sign of attenuation at all and the third and fourth waves are actually increasing in size, the subsequent tsunami waves are likely to become larger.

I think we need to be more careful.