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by foobar__ 3169 days ago
Interestingly, the official website doesn't mention climate change at all, as far as I can see [1].

Instead, it claims that the purpose of the tunnels is to protect the areas surrounding some smaller rivers upstream of Tokyo, which are on flood plains and regularly used to get flooded (no climate change required, just regular rain season/typhoon does this). Now due to urban sprawl more people want to live there, exacerbating the problem and creating the need for this system.

I do not doubt that climate change is happening. I just don't like articles with such a clear agenda in the background, especially when the official sources contradict the statements.

[1] http://www.ktr.mlit.go.jp/edogawa/gaikaku/intro/01intro/inde...

(Please correct me if I'm wrong or I missed something.)

4 comments

Also too, of course you should build your "prevent floods from wrecking our shit" system to handle floods "beyond anything we've seen before". Building it to handle less than what you've seen before would be stupid.
> Building it to handle less than what you've seen before would be stupid.

Let me tell a second hand anecdote of a Burmese village.

It was a rather small collection of huts raised on tall poles. But it was a village none the less.

All paths in the village were laid out with a connected mass of wood. Along the path were sticks, rising pretty high up in the air. Somewhere along the top of the sticks were a lot of cuts made out in the wood, at various heights. By a knife or so.

In the dry season, this path laid on the ground to be walked on. You didn't have to walk on it of course, since the surrounding dirt was dry.

In the wet season however, floods often came. And so, they raised the path up along the sticks so that it became a water bridge for when floods came. They raised it to the level of the highest cuts that were made in the sticks. A very reasonable thing to do, in order to connect the village in times of crisis, without using boats.

Interestingly, however was the background of the cuts. Each cut represented a water height that had some time ago been the highest the flood had become. So each season, they only raised the water bridge to the level of the worst flood they had experienced.

They did not have a margin.

While they didn't prepare for less than what they had previously seen, they only prepared for the worst flood in history, and not the worst flood in history + a margin.

Probably going over the margin would be a matter of wet feet and moving some bamboo which wouldn't be as big a deal as flooding Tokyo.
Were the flood waters raging? Or placid?

Did they have room on the uprights to tie the cross members higher? Maybe the flood water held the wood up (buoyancy) and the uprights were there as anchors.

How did they raise the wood? I imagine it weighed a lot.

Interesting story. Never knew that and I am a Burmese.
That isn't entirely true. How much is it worth to upgrade from a "once every 500 years" system to a "once every 5000 years" system? If it's more than the expected damages...
Well if my country floods its all over, considering we're under sea level the water may never leave.

And I can imagine Japan doesn't want to risk Tokio.

When you start talking truly cataclysmic events, the value of the physical infrastructure at risk will be dwarfed by the human lives. In 2016, the assessed value of all real estate in Manhattan crossed the $1 trillion threshold (which of course leaves out the bridges, the subways, the personal property...) At a value of $9.1 million / life, there are $77.7 trillion worth of humans in New York City.

If there's a natural disaster which would wipe out the population of New York once every 5000 years, we should be willing to spend $15 billion per year to prevent it.

This official interview mentions the intended purpose and use over time.

https://www.travel.co.jp/guide/article/5796/

To protect from climate change and the increased risk of flooding.

Because the reason is building codes, cutting green areas. Flooding is almost always related to changes upriver. Storms and climate change related water level rises are a danger, but not the main reason.
Isn't it an agenda to call the consensus reality an "agenda"? I'm not being facetious, but that discourse has fallen the point where simple statements of reality are politicized has dumbed the entire discourse.
I can only speak for myself, but analogously, I have no disagreement when the anti-vaccination contingent paints the rest of us as having an "agenda" when we post stories about horrible flu outbreaks. Herd immunity and total extinction of certain viruses are definitely an "agenda" I will own up to supporting.
Calling it a consensus reality is also showing an agenda - trying to make it sound more certain than it is, which is to push the agenda of saving people from possible harm of future climate change by fooling them into believing it's certain because they're not competent enough to assess the risk of uncertain things. I'm not complaining about trying to do good, but it's not science, it's belief and it might be wrong.

The rest of science doesn't get described so confidently because people don't care if the general public believes it or not. If you're interested in understanding, not politicizing, then it doesn't matter if there's a consensus or not. Look at the history of consensuses about how nature works to see how unhelpful they are at determining what reality is.

> The rest of science doesn't get described so confidently

Um what? I feel like you haven't spent 10 minutes in a physics class. As someone who spent many years studying physics, you have to get within range of the quantum level before people in that field start feeling a little shaky in their beliefs.

The history of consensuses? Yes, please, you should do that, because it has gotten us quite far given the constraints of time. There are so many crackpot ideas that are thankfully rarely explored due to consensus.

Things that were described confidently for centuries (or less):

  1.  The earth is flat.
  2.  The sun revolves around the earth.
  3.  Fire is an element.
  4.  They have chemical/nuclear weapons.
  5.  No one can enter the search market; AltaVista owns the market.
  6.  Pets.com can't fail - look at who is invested and how big is the market.
  7.  Noone will ever need more than 640K of ram.
  8.  There is a world market for maybe 5 computers.
etc. Who cares how solid the consensus is - what matters is facts and truth.
Bill Gates denies making that 640K statement, and there's no clear evidence he ever said it:

https://quoteinvestigator.com/2011/09/08/640k-enough/

There's also no clear evidence that Thomas Watson ever made the world market for five computers statement:

https://en.wikipedia.org/wiki/Thomas_J._Watson#Famous_attrib...

Congrats. You poked a hole in the meta-consensus, proving the point.

You ignore the others, that dogma leads to shallow thinking.

All the world is the blend of chaos and order; acceptance and rejection, yin and yang. Your contribution helps drive the analytical consideration of acceptance or rejection.

Scientists were widely confident about the correctness of Newton's 2nd law and the universal law of gravitation up till the late 1800s/early 1900s. Then Einstein showed their limitations/incorrectness. You can't look at contemporary modern consensuses because if it's a consensus, it'll look like it's right until the future when/if it's proven wrong.

Philosophy of science says we can't prove theories (of a certain type, which includes most of physics), only disprove them. So there aren't scientific truths, just current best theories.

Many cultures had religious myths about the history of the world which they widely believed.

I'm not saying that people who disagree with the consensus are necessarily right, or even that we should bother to listen to them - just that sometimes they might be so consensus isn't a reason to judge something as true.

> Scientists were widely confident about the correctness of Newton's 2nd law and the universal law of gravitation up till the late 1800s/early 1900s. Then Einstein showed their limitations/incorrectness.

While Einstein revised them, the Newtonian equations are correct enough that they are still generally used for all kinds of things.

If that the best example you can use to make the argument that the current scientific consensus could be wide off the mark, you've done more to refute your argument than advance it.

Bloodletting. It's honestly trivial to find examples of where science was wrong. I'm not going to research them for you if you'll make up ad-hoc reasons to reject them.

Obviously I can't give an example of current consensus being likely wrong because if I knew that, scientists would too and it wouldn't be the consensus.

Here's a snarky example though. See if you can find the flaw in it - current consensus among scientists is that you can't prove causation without doing an experiment - in particular you can't prove it using historical data. This is an obstacle to medical research since ethics impedes controlled experiments on people and it's part of why nutrition advice is frequently wrong (there you go for even more examples). But climate scientists have apparently done just that - themselves demonstrating that either the consensus is wrong or they're wrong. Either way, a consensus is wrong.

These are just an arguments to show how wrong consensus can be though - in reality I'm pretty sure that climate scientists don't acutally believe they're right without any doubt. It will be politics and attempts to manipulate people that changes confidence values into supposed certainty.

How uncertain should man-made global warming sound, in your opinion? You're speaking in gross generalities, perhaps getting some hard numbers. What I've read is that nearly 100% of publishing researchers in the area agree on it (high 90's).

...Actually, it's 97%. I found the paper, which describes the data set and their methodology: http://iopscience.iop.org/article/10.1088/1748-9326/11/4/048...

More helpful than the percentage of scientists who think it's true (a bizarre metric in science) would be the confidence they place on that conclusion. It can't be exactly 100%. Showing causation is notoriously hard, especially when you can only look at historical data, and even more so when there's only one example (one case of humans causing global warming).
This figure gets trotted out all the time and it's tiresome because it is so unconvincing to anyone who is even a bit sceptical.

That's a bit like asking what percentage of Christian priests believe God exists. There's kind of a selection bias there.

More helpful are broader surveys including earth scientists, geologists, etc, which (as I recall, not having the source handy) come up much more conflicted, close to 50% disagreement on various critical questions.

There also the issue of what questions are asked. It's easy to ask, 'is the climate changing', get a near-unanimous response to this near-tautological statement, and declare victory. But that question has nothing to do with any real disagreements real people are having.

The actual questions at hand are much more delicate. First among them is the question of what question we should even be asking.

> More helpful are broader surveys including earth scientists, geologists, etc,

Wait...while i agree that the methodology that gives 97% suffers a selection bias, I don't agree with the above. I would not trust a survey of priests about the existance of God, but I'd prefer their thoughts on the existance of a particular book of the bible than a survey of choir members.

Science is huge and detailed. I'd not trust geologists over physicists about physics. I acknowledge that physicists are not 100% correct, but that doesn't make non-physicists suddenly more likely to be correct.

I can see your point if the claim is 97% of scientists, but the claim is about climate scientists, because they determine the consensus on the topic.

What method of saying whether or not there is a consensus would you accept that doesn't involve bringing in people with no knowledge or experience with the topic?

You mentioned a 50%ish figure for scientists. Do you have a citation? Even if I think the result unconvincing (based on tjis limited info) I'd like to see their methodology and sample size.

His figure is probably based on a study specifically addressed in link I provided. Look for "Bray and von Storch (2007) and Bray (2010)" and the critique of their results and methodologies.
That there is a scientific consensus is not an agenda, it's a fact.