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Swept away: $500k sand dune built to protect US homes disappears in days

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Re: Swept away: $500k sand dune built to protect US homes disappears in days

#91

Post by blagie »

pixl97 wrote: post #82
blagie wrote: post #74

Earlier quoted context omitted.

I'm not sure water needs to be diverted, per se. The problem isn't baseline water level but waves, and especially large waves, and sand washing away. It seems like the solutions would involve some combination of: * Breakwaters, to equalize the water levels and reduce the waves * A few meters inland, some kind of wall (firmer than sand) which doesn't wash away, so a bigger wave doesn't impact homes * Perhaps some kind…

You seemingly don't understand the costs and long term effects of what you're asking. Just dumping sand on the beach is positively cheap compared to the hundreds of millions you're asking for. Also, building a wall near the ocean is possibly the worst idea you could ever do. Please research the interaction between air, water, and sand to learn this is how you make a massive hole that swallows everything. The same is…

Glad to do research! Can you give me pointers?

This seems like the sort of problem we ought to learn to solve. That's why I'd like us to try things, and I'm happy to have a little bit of my tax dollars involved. This problem will only be more and more common.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#92

Post by acdha »

snapplebobapple wrote: post #84
acdha wrote: post #65

Earlier quoted context omitted.

> It's mostly not even climate change Let me amend that: it’s not just climate change but climate change is like a catalyst for the existing problem. Higher sea level, greater storm intensity and frequency, and other ecological impacts (e.g. native vegetation might not control erosion as well due to changing conditions or invasive pests) all mean we get the harder versions of the problem and have deal with more crise…

Its more like this was inevitable regardless of climate change on the time period the average housing stock lasts, so building there and expecting this to stay as is was inevitably stupid regardless of climate change.

Higher sea levels are a good counter example to your point. Nobody thinks of normal housing lasting the thousands of years that process takes when you are think in terms of ice ages and warming periods, but a relatively modest rise makes a big difference when you’re thinking about things like how much a given house is exposed to storm surge.

Similarly, forest fires are always a risk but the fires are bigger, more frequent, and hotter when climate change had been drying out previously wet regions. That means society needs to plan for huge increases in response capacity in much larger regions than previously was the case, so again while it’s technically possible for there to be a fire anywhere those are very different situations from the prospective of everyone on defense.

Think of it like the way armies had to change going from flintlocks to automatic weapons, only we’re doing it much faster and are going to have to make hard sacrifices.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#93

Post by wakawaka28 »

stickybit wrote: post #89
snapplebobapple wrote: post #84

Earlier quoted context omitted.

Its more like this was inevitable regardless of climate change on the time period the average housing stock lasts, so building there and expecting this to stay as is was inevitably stupid regardless of climate change.

The reality is that climate change is resulting in 100 year events becoming 10 year events. Yes, the barrier probably would have been washed away _eventually_ irrespective of our changing climate, but sea levels are rising (104mm since 1993) and the frequency and intensity of extreme weather events is increasing. Everything that is now happening occurs in the context of our destabilizing climate. Given this, I'm not…

Or you know, maybe people are too stupid to estimate probabilities like that. Our history is too short to really know what is normal and what is out of line. In geological terms, we are still very much coming out of an ice age and far from peak temperatures that we know have happened before.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#94

Post by defrost »

wakawaka28 wrote: post #93
stickybit wrote: post #89

Earlier quoted context omitted.

The reality is that climate change is resulting in 100 year events becoming 10 year events. Yes, the barrier probably would have been washed away _eventually_ irrespective of our changing climate, but sea levels are rising (104mm since 1993) and the frequency and intensity of extreme weather events is increasing. Everything that is now happening occurs in the context of our destabilizing climate. Given this, I'm not…

Or you know, maybe people are too stupid to estimate probabilities like that. Our history is too short to really know what is normal and what is out of line. In geological terms, we are still very much coming out of an ice age and far from peak temperatures that we know have happened before.

> In geological terms, we are still very much coming out of an ice age

In geological terms, AGW aside, the earth was still very much within the Late Cenozoic Ice Age and has been for 34 million years.

In glaciation terms the earth was swinging out of an inter glaciation period and due to return to glaciation and decreasing global tempretures and increasing ice coverage.

Thanks to human activity increasing the insulation attributes of the atmosphere mean tempretures are increasing and global mean tempretures will increase past what we (as a human species) have experienced in our brief time on the planet.

> far from peak temperatures that we know have happened before.

It's true - we're a long way from living on the surface of a near molten ball of rock with no breathable atmosphere, as the earth once was.

[1] https://en.wikipedia.org/wiki/Late_Cenozoic_Ice_Age

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#95

Post by wakawaka28 »

defrost wrote: post #94
wakawaka28 wrote: post #93

Earlier quoted context omitted.

Or you know, maybe people are too stupid to estimate probabilities like that. Our history is too short to really know what is normal and what is out of line. In geological terms, we are still very much coming out of an ice age and far from peak temperatures that we know have happened before.

> In geological terms, we are still very much coming out of an ice age In geological terms, AGW aside, the earth was still very much within the Late Cenozoic Ice Age and has been for 34 million years. In glaciation terms the earth was swinging out of an inter glaciation period and due to return to glaciation and decreasing global tempretures and increasing ice coverage. Thanks to human activity increasing the insulat…

Ok you got me. I meant in the last few hundred million years it has been way hotter than today. Life existed and thrived back then as well. We are coming out of an ice age and temperatures must necessarily increase as a result, regardless of any presumed impact humans have on that process. This may be interfering with estimations of the impact of CO2 on our atmosphere. I'm not claiming to be an expert on this but I am skeptical of people who claim to be experts on this, as alarmism inherently boosts their careers.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#96

Post by defrost »

wakawaka28 wrote: post #95
defrost wrote: post #94

Earlier quoted context omitted.

> In geological terms, we are still very much coming out of an ice age In geological terms, AGW aside, the earth was still very much within the Late Cenozoic Ice Age and has been for 34 million years. In glaciation terms the earth was swinging out of an inter glaciation period and due to return to glaciation and decreasing global tempretures and increasing ice coverage. Thanks to human activity increasing the insulat…

Ok you got me. I meant in the last few hundred million years it has been way hotter than today. Life existed and thrived back then as well. We are coming out of an ice age and temperatures must necessarily increase as a result, regardless of any presumed impact humans have on that process. This may be interfering with estimations of the impact of CO2 on our atmosphere. I'm not claiming to be an expert on this but I a…

> Life existed and thrived back then as well.

Hate to break it to you, but humans are not stromatolites.

Humans have been about for two million years and have evolved to live in recent climatic conditions and to thrive in the extremely relatively stable Holocene.

> We are coming out of an ice age

On what evidence?

By the record we are in an ice age (do see and read my prior link) and not only were we expected to stay in that ice age but were expected to return to increased glaciation (ie decreasing tempretures).

The only reason we are coming out of an ice age is due to human activity increasing the bulk insulation properties of the atmosphere.

> I'm not claiming to be an expert on this

I've spent four decades in geophysical exploration developing instruments and software for mapping earths energy and mineral resources for extraction.

I'm also not claiming to be an expert but I have some exposure to continent and global scale modelling of gravity, radiometrics, magnetic fields, tidal movements, drift, etc.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#97

Post by wakawaka28 »

defrost wrote: post #96
wakawaka28 wrote: post #95

Earlier quoted context omitted.

Ok you got me. I meant in the last few hundred million years it has been way hotter than today. Life existed and thrived back then as well. We are coming out of an ice age and temperatures must necessarily increase as a result, regardless of any presumed impact humans have on that process. This may be interfering with estimations of the impact of CO2 on our atmosphere. I'm not claiming to be an expert on this but I a…

> Life existed and thrived back then as well. Hate to break it to you, but humans are not stromatolites. Humans have been about for two million years and have evolved to live in recent climatic conditions and to thrive in the extremely relatively stable Holocene. > We are coming out of an ice age On what evidence? By the record we are in an ice age (do see and read my prior link) and not only were we expected to stay…

This page has some good general information that you ought to be aware of before talking to people about this topic: https://www.ces.fau.edu/nasa/module-3/temperature-trend-chan... In short, the planet's temperature shifts wildly in geological time, even in a human time scale. Our written language and species may eventually survive long enough to convey all of this information past the next ice age, whenever that is to happen.

>The only reason we are coming out of an ice age is due to human activity increasing the bulk insulation properties of the atmosphere.

The climate is naturally cyclical, as explained in my reference above and many other academic sources. Again I'm not suggesting there is no human impact but that this may be difficult to isolate, no matter how confident various researchers claim to be in their models. We humans have lived through an ice age only 20k years ago and that ice age has been ending ever since, and not because of us. As an armchair geologist you should know about that as well as the Little Ice Age much more recent than that. This looks interesting: https://www.history.com/news/ice-age-human-survival

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#98

Post by misja111 »

pixl97 wrote: post #62
misja111 wrote: post #49

Earlier quoted context omitted.

The Dutch would disagree

Two things.... 1. They spend something like 1.5% of their GDP so they can double the size of their country. This works ok for small countries, but not large ones (think more of city protection for larger places). 2. This will eventually get them sued in international court when one of their projects affects surrounding countries. The ocean is filled with butterfly effects.

> 2. This will eventually get them sued in international court when one of their projects affects surrounding countries. The ocean is filled with butterfly effects.

That's bizarre. Do you really think the Dutch will at some point get sued because of the dikes they have built to keep out the water? Maybe somebody should warn them, I can assure you that nobody in the Netherlands has ever considered that possibility ..

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#99

Post by pixl97 »

blagie wrote: post #91
pixl97 wrote: post #82

Earlier quoted context omitted.

You seemingly don't understand the costs and long term effects of what you're asking. Just dumping sand on the beach is positively cheap compared to the hundreds of millions you're asking for. Also, building a wall near the ocean is possibly the worst idea you could ever do. Please research the interaction between air, water, and sand to learn this is how you make a massive hole that swallows everything. The same is…

Glad to do research! Can you give me pointers? This seems like the sort of problem we ought to learn to solve. That's why I'd like us to try things, and I'm happy to have a little bit of my tax dollars involved. This problem will only be more and more common.

If you want a book that directly faces the problem look at "Pitfalls of Shoreline Stabilization: Selected Case Studies".

Of course you'll want to balance that out with books that just talk about the general challenges and successes, in which I'd recommend just looking at books.google.com on writings by the US Army Corp of Engineers. They talk about practical mitigations for different types of erosion.

Most success stories are going to be based on things like using plants/growth to trap and build sand, which typically means lowering human access to the beach and ensuring tall things that interrupt wind flow are not near the beach. For example mangroves in climates that allow them to grow.

There are also plenty of examples poing out by the C of E on things that cannot be solved. If you built a city near a portion of the beach that was eroding long before humankind appeared in to the picture, all you can do is slow that erosion and at great expense. The ocean is far more powerful than you can imagine.

Re: Swept away: $500k sand dune built to protect US homes disappears in days

#100

Post by blagie »

pixl97 wrote: post #99
blagie wrote: post #91

Earlier quoted context omitted.

Glad to do research! Can you give me pointers? This seems like the sort of problem we ought to learn to solve. That's why I'd like us to try things, and I'm happy to have a little bit of my tax dollars involved. This problem will only be more and more common.

If you want a book that directly faces the problem look at "Pitfalls of Shoreline Stabilization: Selected Case Studies". Of course you'll want to balance that out with books that just talk about the general challenges and successes, in which I'd recommend just looking at books.google.com on writings by the US Army Corp of Engineers. They talk about practical mitigations for different types of erosion. Most success st…

Thank you!
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