toldailytopic: Do you believe mankind is causing global warming?

[Stripe]

There are many rising and many being worn down. Do you want numbers, surface area, what?

Erosion has nothing to do with this discussion, Barbarian. It pays to understand the idea presented before you try to ridicule it. :thumb:

I reckon the vast majority of major mountain ranges are probably sinking around the world. Got anything that says otherwise?

Where are the contemporary orogenies? As far as I can tell we have the Kaikoura range, the Mediterranean and perhaps the Andes. Would you regard that as a majority?

 

[The Barbarian]

Erosion has nothing to do with this discussion, Barbarian.

That's how mountains get lower, Stipe. I thought you knew. Isostasy determines how deep into the mantle the mountains go. Think about a small log. It doesn't go deep into the water. Then think about a much bigger log. It goes deeper by the proportion of the two sizes. Big mountains have deeper roots. As they erode away, isostasy makes them rise up in the mantle.

Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

It pays to understand the idea presented before you try to ridicule it.

It pays even more to understand an idea before you present it, Stipe.

I reckon the vast majority of major mountain ranges are probably sinking around the world. Got anything that says otherwise?

Show me your data on how deep they go into the mantle and how that's changing. And we'll take a look. The Himalayas, the Andes, the Cascades, and some others are going deeper into the mantle now. But they are also getting higher. The same things that make them higher also make them sink deeper.

Do you have a point here?

 

[Stripe]

That's how mountains get lower, Stipe. I thought you knew. Isostasy determines how deep into the mantle the mountains go. Think about a small log. It doesn't go deep into the water. Then think about a much bigger log. It goes deeper by the proportion of the two sizes. Big mountains have deeper roots. As they erode away, isostasy makes them rise up in the mantle.

:dizzy:

Stick to your day job, mate.

Isostacy is the only issue of relevance. Erosion is a complete non-issue in this discussion. Which mountain ranges are sinking and which are rising on Earth today? Which do you think is the more prevalent action?

Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

Oh. So now continents can rise? :chuckle:

Please stick to what I asked. We're trying to determine which mountain ranges are rising or sinking.

It pays even more to understand an idea before you present it, Stipe.

And it pays to understand it before you accuse another of not understanding. :thumb:

Show me your data on how deep they go into the mantle and how that's changing. And we'll take a look. The Himalayas, the Andes, the Cascades, and some others are going deeper into the mantle now. But they are also getting higher. The same things that make them higher also make them sink deeper.

What measurements are you referring to here?

Do you have a point here?

Sure. Read my first post again. :thumb:

 

[The Barbarian]

Barbarian observes:
That's how mountains get lower, Stipe. I thought you knew. Isostasy determines how deep into the mantle the mountains go. Think about a small log. It doesn't go deep into the water. Then think about a much bigger log. It goes deeper by the proportion of the two sizes. Big mountains have deeper roots. As they erode away, isostasy makes them rise up in the mantle.

Stick to your day job, mate.

It's demonstrably true. We can, by using seismic waves, determine how deep the crust is below the surface:

To understand isostasy let’s review what we know about the shallow interior of the earth and how we know it. Our main source of information is seismology. Using earthquake waves we can map out the thicknesses and seismic velocities of the interior.

The wave velocities can be compared to values measured in the laboratory to tell us what kinds of rocks make up the layers. Knowing the velocities and the rock types, we can use lab data to estimate densities of the layers. This in turn leads to testable predictions of the local values of “g”, the acceleration of gravity; other things being equal, g is high where the rocks are dense and less where they are less dense. We can check our cross-section by
looking at “xenoliths”, rocks brought up from depth by volcanic eruptions. As a result of all this work we have a clear picture of the upper few hundred kilometers of the earth. The continental crust averages about 37 km in thickness but ranges from as little as 20 km on rifted continental margins to almost 80 km in the highest mountains. In general the crust is thick where the elevation is high and thin where the elevation is low. The composition of the crust ranges from granitic at the top to gabbroic at the base.
http://earth.unh.edu/esci401/docs/class_38.pdf

Erosion is a complete non-issue in this discussion.

No, you've got that wrong, too:

On a longer time scale we see that the life of mountains is prolonged by isostasy. Although erosion acts to reduce mountain elevations, it also causes isostatic uplift (reduction of load) that partially cancels the reduction of elevation. Thus mountains remain as high topographic features for much longer than we would expect from erosion rates and initial elevation alone.
(same source)

Surprise.

Which mountain ranges are sinking and which are rising on Earth today?

As you see, any mountain range that is getting higher, is sinking deeper into the mantle. Any mountain range that is getting lower, is rising up out of the mantle. I suppose you actually mean "which mountains are getting higher, and which are getting lower." But it's hard to say because you don't have the process clear in your own mind.

Barbarian observes:
Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

Oh. So now continents can rise?

Parts of them. It's like piece of wood. A certain percentage of it is sunk into the water. If it's irregular, when it turns, different parts get higher or lower, but the percent above water doesn't change. You're having difficulty getting a grasp on the way it works.

Barbarian suggests:
It pays even more to understand an idea before you present it, Stipe.

And it pays to understand it before you accuse another of not understanding.

No sense of irony, at all...

Barbarian observes:
Show me your data on how deep they go into the mantle and how that's changing. And we'll take a look. The Himalayas, the Andes, the Cascades, and some others are going deeper into the mantle now. But they are also getting higher. The same things that make them higher also make them sink deeper.

What measurements are you referring to here?

See above. Make up your mind what you want to find out.

 

[Stripe]

Barbarian observes:That's how mountains get lower, Stipe. I thought you knew. Isostasy determines how deep into the mantle the mountains go. Think about a small log. It doesn't go deep into the water. Then think about a much bigger log. It goes deeper by the proportion of the two sizes. Big mountains have deeper roots. As they erode away, isostasy makes them rise up in the mantle.It's demonstrably true. We can, by using seismic waves, determine how deep the crust is below the surface:FONT="Comic Sans MS"]To understand isostasy let’s review what we know about the shallow interior of the earth and how we know it. Our main source of information is seismology. Using earthquake waves we can map out the thicknesses and seismic velocities of the interior.The wave velocities can be compared to values measured in the laboratory to tell us what kinds of rocks make up the layers. Knowing the velocities and the rock types, we can use lab data to estimate densities of the layers. This in turn leads to testable predictions of the local values of “g”, the acceleration of gravity; other things being equal, g is high where the rocks are dense and less where they are less dense. We can check our cross-section bylooking at “xenoliths”, rocks brought up from depth by volcanic eruptions. As a result of all this work we have a clear picture of the upper few hundred kilometers of the earth. The continental crust averages about 37 km in thickness but ranges from as little as 20 km on rifted continental margins to almost 80 km in the highest mountains. In general the crust is thick where the elevation is high and thin where the elevation is low. The composition of the crust ranges from granitic at the top to gabbroic at the base. /FONT]url]htt p://earth.unh.edu/e sci401/docs /class_38.pdf[/url]No, you've got that wrong, too:FONT="Comic Sans MS"]On a longer time scale we see that the life of mountains is prolonged by isostasy. Although erosion acts to reduce mountain elevations, it also causes isostatic uplift (reduction of load) that partially cancels the reduction of elevation. Thus mountains remain as high topographic features for much longer than we would expect from erosion rates and initial elevation alone.[/FONT](same source)Surprise.

:doh:

Slow down, Barbarian. You do not even understand what you're trying to discuss. What you do sound like is you wish you had a class full of first year students and you are teaching them something new. :chuckle:

As you see, any mountain range that is getting higher, is sinking deeper into the mantle. Any mountain range that is getting lower, is rising up out of the mantle. I suppose you actually mean "which mountains are getting higher, and which are getting lower." But it's hard to say because you don't have the process clear in your own mind.

Or you could just answer the question. Which ranges are sinking and which are rising? Put a GPS locator on top of them and tell us which are going up and which are going down.

Simple.

Barbarian observes:Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

Yeah .. after how many years?

I don't think so, sonny. :chuckle:

The Amazon basin responds rapidly and noticeably to the accumulation of water. Your evidence supports a "recent" and very dramatic change.

It pays even more to understand an idea before you present it, Stipe.

It pays to understand that which you are trying to refute before you spend hours collecting material for your posts. :thumb:

 

[The Barbarian]

Slow down, Barbarian. You do not even understand what you're trying to discuss. What you do sound like is you wish you had a class full of first year students and you are teaching them something new.

Judging by your befuddled responses and your failure to answer my questions, all this blindsided you once again.

Barbarian observes:
As you see, any mountain range that is getting higher, is sinking deeper into the mantle. Any mountain range that is getting lower, is rising up out of the mantle. I suppose you actually mean "which mountains are getting higher, and which are getting lower." But it's hard to say because you don't have the process clear in your own mind.

Or you could just answer the question. Which ranges are sinking and which are rising?

You still seem unable to decide what you mean by that. Let me do it simpler:

The Himalyas are sinking into the mantle as they pile up from the (measurable) collision of India and the rest of Asia. They are also getting taller. So, are they sinking or rising?

Put a GPS locator on top of them and tell us which are going up and which are going down.

Turns out, GPS isn't so good at vertical movments in the rate of centimeters per year. My Garmin, for example, is accurate to about 20 meters, vertically. Like measuring the width of a hair with a yardstick. But do tell us whether we should consider them sinking, because they are going deeper into the mantle, or rising, because they are getting taller.

Simple

Not so simple:
http://en.wikipedia.org/wiki/Geoid

Barbarian observes:Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

Yeah .. after how many years?

It's been going on pretty much continuously for the last 13,000 years or so.

I don't think so, sonny.

You don't think much at all, Stipe. Unless you're past retirement age, you probably shouldn't be calling me "sonny."

The Amazon basin responds rapidly and noticeably to the accumulation of water.

Yeah. Water flows a lot more readily than the mantle. Go figure.

Your evidence supports a "recent" and very dramatic change.

About 13,000 years. Would you like to learn how we know?

Barbarian chuckles:
It pays even more to understand an idea before you present it, Stipe.

Let me know whether you think the Himalayas are sinking or rising, O.K.?

 

[eameece]

Really eemee?

That's the best you can do?

Not even one little fact?

How about this;

It is a fact, sir, that you are an idiot.

 

[some other dude]

You may well think that but it doesn't excuse your inability to provide facts to support your claims. :idunno:

 

[Stripe]

Judging by your befuddled responses and your failure to answer my questions, all this blindsided you once again. Barbarian observes: As you see, any mountain range that is getting higher, is sinking deeper into the mantle. Any mountain range that is getting lower, is rising up out of the mantle. I suppose you actually mean "which mountains are getting higher, and which are getting lower." But it's hard to say because you don't have the process clear in your own mind. You still seem unable to decide what you mean by that. Let me do it simpler: The Himalyas are sinking into the mantle as they pile up from the (measurable) collision of India and the rest of Asia. They are also getting taller. So, are they sinking or rising? Turns out, GPS isn't so good at vertical movments in the rate of centimeters per year. My Garmin, for example, is accurate to about 20 meters, vertically. Like measuring the width of a hair with a yardstick. But do tell us whether we should consider them sinking, because they are going deeper into the mantle, or rising, because they are getting taller. Not so simple:[ur l]http://en. wikipedia.org/wiki/ Geoid[/url]Barbarian observes:Because of the weight of the glaciers in the last ice age, much of North America was depressed by the addtional weight. It has not fully recovered; much of it is still rising up. The upper Midwest and Southern Canada, for example, are still rising from their lowered position during the ice ages. They are also getting warmer. That seems to contradict your new idea.

So what is being used to measure vertical movement?

It's been going on pretty much continuously for the last 13,000 years or so.

Then it should have reached an equilibrium by now.

You don't think much at all, Stipe. Unless you're past retirement age, you probably shouldn't be calling me "sonny."

I'll call 'em as I see 'em.

Yeah. Water flows a lot more readily than the mantle. Go figure.

It's not the water being measured, dummy.

It pays even more to understand an idea before you present it, Stipe.

It pays to know what you're trying to refute before you start lecturing on irrelevant issues.

Let me know whether you think the Himalayas are sinking or rising, O.K.?

Which way are the peaks going?

 

[The Barbarian]

So what is being used to measure vertical movement?

Over thirteen thousand years, a few centimeters per year adds up. Roughly in kilometers.

Barbarian observes:
It's been going on pretty much continuously for the last 13,000 years or so.

Then it should have reached an equilibrium by now.

The mantle is not actually liquid. It's very hot rock and it deforms quite slowly over time.

Barbarian chuckles:
You don't think much at all, Stipe. Unless you're past retirement age, you probably shouldn't be calling me "sonny."

I'll call 'em as I see 'em.

Or don't see them.

Barbarian, regarding why isostasy works so slowly:
Yeah. Water flows a lot more readily than the mantle. Go figure.

It's not the water being measured, dummy.

That's what I just told you, Stipe.

Barbarian suggests:
You don't seem to have this clear in your mind. If mountains are rising, they are sinking into the mantle. If they are being worn down, they are rising up out of the mantle.

Let me know whether you think the Himalayas are sinking or rising, O.K.?

Which way are the peaks going?

They are rising.

 

[Stripe]

Over thirteen thousand years, a few centimeters per year adds up. Roughly in kilometers.

And you've been using what to measure this? A sextant?

Barbarian observes:
It's been going on pretty much continuously for the last 13,000 years or so

No, it hasn't.

They are rising.

:BRAVO: A straightforward answer. Congratulations.

How is that upward motion being measured?

 

[The Barbarian]

Originally Posted by The Barbarian View Post
Over thirteen thousand years, a few centimeters per year adds up. Roughly in kilometers.

And you've been using what to measure this? A sextant?

Relative elevations of rock strata in different places.

Barbarian observes:
It's been going on pretty much continuously for the last 13,000 years or so

No, it hasn't.

Yep. Learn about it here:
During the last glacial period, much of northern Europe, Asia, North America, Greenland and Antarctica were covered by ice sheets. The ice was as thick as three kilometres during the last glacial maximum about 20,000 years ago. The enormous weight of this ice caused the surface of the Earth's crust to deform and warp downward, forcing the fluid mantle material to flow away from the loaded region. At the end of the ice age when the glaciers retreated, the removal of the weight from the depressed land led to slow (and still ongoing) uplift or rebound of the land and the return flow of mantle material back under the deglaciated area. Due to the extreme viscosity of the mantle, it will take many thousands of years for the land to reach an equilibrium level.

Studies have shown that the uplift has taken place in two distinct stages. The initial uplift following deglaciation was rapid (called "elastic"), and took place as the ice was being unloaded. After this "elastic" phase, uplift proceeded by "slow viscous flow" so the rate decreased exponentially after that. Today, typical uplift rates are of the order of 1 cm/year or less. In northern Europe, this is clearly shown by the GPS data obtained by the BIFROST GPS network.[1] Studies suggest that rebound will continue for about at least another 10,000 years. The total uplift from the end of deglaciation depends on the local ice load and could be several hundred metres near the centre of rebound.
http://en.wikipedia.org/wiki/Post-glacial_rebound

(Stipe is a bit befuddled by geologic terms, and wants a simpler answer)

Barbarian simplifies:
They are rising.

A straightforward answer. Congratulations.

Of course, it's never that simple in the real world, but in general, that's the case.

How is that upward motion being measured?

Centimeters per year. Formerly, it was done by surveying, but very recently, improvements in GPS has permitted special instruments to check those numbers.

 

[Stripe]

Relative elevations of rock strata in different places.

I see.

Sounds like you have zero capacity to answer the question you've very successfully trampled into obscurity.

Centimeters per year. Formerly, it was done by surveying, but very recently, improvements in GPS has permitted special instruments to check those numbers.

What special instruments?

 

[eameece]

Yet another country torn by the climate change you right-wingers voted for. South Korea, your ally, now devastated by floods; at least 32 killed and no end in sight.
http://www.reuters.com/article/2011/07/27/us-korea-landslide-idUSTRE76Q0F920110727

 

[Frank Ernest]

Yet another country torn by the climate change you right-wingers voted for. South Korea, your ally, now devastated by floods; at least 32 killed and no end in sight.
http://www.reuters.com/article/2011/07/27/us-korea-landslide-idUSTRE76Q0F920110727

:darwinsm:

 

[The Barbarian]

In fact, no particular incident of weather can be attributed to climate change. If we lambaste deniers for pointing to a cold spell as proof that climate warming is a fraud, we should be particularly careful not to do the same thing.

 

[The Barbarian]

Originally Posted by The Barbarian View Post
Relative elevations of rock strata in different places.

I see.

Sounds like you have zero capacity to answer the question you've very successfully trampled into obscurity.

Did you never wonder how geologists could find elevations before GPS?

So uplift or sinking can be measured by surveying any particular formation with reference to sea level.

Stipe wonders how:
Centimeters per year. Formerly, it was done by surveying, but very recently, improvements in GPS has permitted special instruments to check those numbers.

What special instruments?

GPS units, able to use different satellites so as to improve the angle of reference and get a better result.

 

[Stripe]

GPS units, able to use different satellites so as to improve the angle of reference and get a better result.

OK. So elevation can be measured by GPS now...

Are the mountain ranges around the world generally sinking or rising? I reckon they are generally sinking.

 

[The Barbarian]

OK. So elevation can be measured by GPS now...

It doesn't work the way your Tomtom does, but it uses satellites.

Are the mountain ranges around the world generally sinking or rising?

Andes, Himalayas, Cascades, Rocky Mountains are rising. Apparently, at least part of the Appalachians are also pushing up:
http://www.aldha.org/rising.htm

The Alps are still rising. The Eastern Pyrenees are still rising.


Looks like most are coming up. You realize that because of isostasy, those being eroded rapidly will be lifted up as the overlying weight is removed.

I reckon they are generally sinking.

Remember the difference. As mountains grow taller, they sink deeper into the mantle.

 

[Stripe]

Looks like most are coming up. You realize that because of isostasy, those being eroded rapidly will be lifted up as the overlying weight is removed.

That's probably where the two different ideas will have to clash. As I say, erosion is a complete non-issue for the explanation I have given. Thus it's effects would have to be removed in order to make sense of the numbers we might return.

So my prediction is likely incorrect, but possibly only because I didn't consider uplift due to erosion.