What Would Happen to Tokyo If Mount Fuji Erupted?—I Used to Be Excited by Volcanic Ash as a Child

The other day, I watched a government video about preparations for an eruption of Mount Fuji.

Mount Fuji is about 100 kilometers from Tokyo. Even in a major eruption, there is no danger of lava reaching Tokyo or the city being struck by a pyroclastic flow.

Does that mean Tokyo is safe?

Not at all. The problem is volcanic ash.

Depending on the direction of the wind, large amounts of ash could fall on Tokyo and paralyze the city’s essential functions.

Volcanic ash may sound like something that would merely make the city a little dirty, but the reality is far more troublesome.

First, volcanic ash is not ordinary dust or sand. It contains particles like tiny fragments of glass, and inhaling them can damage the respiratory system.

I have asthma, so this is no laughing matter for me. As a child, I might have gone outside to play in it. Now, I would have no choice but to close the windows and stay indoors.

Unlike snow, volcanic ash does not melt.

If it accumulates on roads, cars may be unable to use them. If it washes into drains, it can block them. Wet ash sticking to electrical equipment can cause power outages. Railways, aircraft, and logistics would all be affected.

It would be like covering all of Tokyo in snow that never melts—and that also shuts down electricity and communications.

With snow, you can wait for spring. Volcanic ash has to be cleared away by someone.

As I watched the government video, I thought about what an enormous task that would be.

When Ash from Mount Asama Fell on Tokyo During My Childhood

I actually remember seeing volcanic ash fall on Tokyo.

It happened when Mount Asama erupted while I was a child.

When I arrived at school one morning, ash had settled over the schoolyard and the roads.

Instead of being frightened, however, I found it exciting.

“Wow, it looks like snow!”

To a child living in Tokyo, volcanic ash was simply something unusual. The trouble facing the adults who had to clean it up was none of my concern.

Looking back, I was in a wonderfully carefree position.

The More Convenient Tokyo Becomes, the More Frightening a Shutdown Is

Decades have passed since then.

Tokyo itself now works very differently from the way it did at the time.

Trains, communications, logistics, and payments—almost everything now depends on computers and networks.

If volcanic ash disrupts electrical equipment or transportation, the effects will spread from one system to another.

In the past, even during a power outage, the woman running a neighborhood shop might have calculated your change in her head.

Today, if the checkout system stops working, you may be unable to buy a product even when it is sitting directly in front of you.

The more convenient the city becomes, the greater the disruption when it stops working.

I sincerely hope the national and Tokyo metropolitan governments prepare well. Stories like this make me a little more forgiving toward the public officials I usually do nothing but complain about.

I Would Like Mount Fuji to Sleep a Little Longer

Tokyo is not the only thing that has changed. I have changed too.

I now have asthma, which I did not have as a child.

Back then, I saw volcanic ash and shouted, “Snow!” Today, I would probably be shouting, “Do not open the windows under any circumstances!”

The ash is the same, yet my treatment of it has changed considerably.

No one knows when Mount Fuji will erupt.

If possible, however, I would like it to remain quiet for the rest of my lifetime.

I am not saying that I do not care what happens after that.

I would simply prefer to pass the problem on to the next generation.

I feel rather guilty about postponing not only the pension burden, but the risk of an eruption as well.