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[soundman]

rak sa_ngop, on 2007-04-23 22:45:19, said:

LaoPo, on 2007-04-23 20:49:01, said:

rak sa_ngop, on 2007-04-23 15:32:41, said:

A bit more science in this article. Are there any experts in regional geology, plate tectonics and subsidence rates who wish to comment?

Have a look at 'Bisto's' post in #9, second link; that'll do for you.

LaoPo

Thanks I've copied this from the first link:


quote
Relative sea-level is affected by vertical
land movements caused by tectonic movement,
sedimentation, groundwater and oil extraction.
Warrick et al. (1993) summarized four main
processes affecting sea level changes: (A) glacio-
eustasy, ( emergence/subsidence of land, ©
manmade activity, and (D) ocean-atmosphere
effects (Table 4). These factors vary widely in their
effects on relative changes in sea-level.

Regarding the process ( , vertical land
movements, Yanagi and Akaki (1993) studied sea-
level variation rates from 1950 to 1991 in the East
Asian region. Figure 5, in which the shaded area
denotes where the sea-level falls due to the plate
tectonics, shows that the sea-level has fallen for
the past 40 years in an area including the southern
part of the Sea of Japan, the Korean Peninsula,
Indochina, and the Malay Peninsula.
unquote

So maybe there is some 'method in their madness'!

So you would think that any scientist using the above discussion of the rise and fall of tectonic plates would put forth that the argument that the tectonic plate upon which Thailand and the gulf sit may actually be rising, instead of the absolutely stupid argument that whilst the mean water level in say Alaska will rise, the relative water level in the gulf of thailand will not, leaving a gradual slope between Alaska & Thailand.

"Method to their madness" - grow a brain with some common sense is more to the point.

Cheers,


Soundman.

[kayo]

you guys are slow on the uptake today!!

so i-ll take care of it this time:


thailand: global hub of dry land

[Naam]

whatever sound logic seems to be applied here is flawed. the seas are indeed not level. differences up to two meters exist... that is a fact whether you believe it or not.

[gummy]

soundman, on 2007-04-24 09:52:35, said:

rak sa_ngop, on 2007-04-23 22:45:19, said:

LaoPo, on 2007-04-23 20:49:01, said:

rak sa_ngop, on 2007-04-23 15:32:41, said:

A bit more science in this article. Are there any experts in regional geology, plate tectonics and subsidence rates who wish to comment?

Have a look at 'Bisto's' post in #9, second link; that'll do for you.

LaoPo

Thanks I've copied this from the first link:


quote
Relative sea-level is affected by vertical
land movements caused by tectonic movement,
sedimentation, groundwater and oil extraction.
Warrick et al. (1993) summarized four main
processes affecting sea level changes: (A) glacio-
eustasy, ( emergence/subsidence of land, ©
manmade activity, and (D) ocean-atmosphere
effects (Table 4). These factors vary widely in their
effects on relative changes in sea-level.

Regarding the process ( , vertical land
movements, Yanagi and Akaki (1993) studied sea-
level variation rates from 1950 to 1991 in the East
Asian region. Figure 5, in which the shaded area
denotes where the sea-level falls due to the plate
tectonics, shows that the sea-level has fallen for
the past 40 years in an area including the southern
part of the Sea of Japan, the Korean Peninsula,
Indochina, and the Malay Peninsula.
unquote

So maybe there is some 'method in their madness'!

So you would think that any scientist using the above discussion of the rise and fall of tectonic plates would put forth that the argument that the tectonic plate upon which Thailand and the gulf sit may actually be rising, instead of the absolutely stupid argument that whilst the mean water level in say Alaska will rise, the relative water level in the gulf of thailand will not, leaving a gradual slope between Alaska & Thailand.

"Method to their madness" - grow a brain with some common sense is more to the point.

Cheers,


Soundman.

Also be interesting to hear his theory on Hawaii which by all acoounts and scientific analysis is actually sinking. I wonder if the professor would consider this not to be the real case rather that the sea level is rising at this location and hence creating "a big bump of water in the Pacific

[dumspero]

First, I don't think any of the posters on here have any sound idea whether the professor makes sense or not. This is especially so since these are very technical issues that are sometimes reported by people who don't understand what's being said--so they get it down wrong or take it out of context. A poster has already made this point.

Second, what's the basis to generalize to other professors or Thais, generally? That's just more of the prejudice one sees on here on a regular basis. And please, there's a big difference between criticizing something and making sweeping generalizations. The former is ok if rational, the latter is naked prejudice.

[ThaiGoon]

Dr. Naam, on 2007-04-24 09:57:02, said:

whatever sound logic seems to be applied here is flawed. the seas are indeed not level. differences up to two meters exist... that is a fact whether you believe it or not.

[cdnvic]

And contrary to incorrect information in the other thread on this, the Panama canal does not have locks due to the different levels of the Atlantic and Pacific (Pacific is usually 20cm higher due to prevailing winds and being slightly less dense due to salinity differences), it's because the canal actually travels over mountain lakes and it would have to be cut impossibly deep to run across Panama as a level canal. If it was the 20cm difference that was the issue a simple lock at the entrance would suffice.

[taxexile]

6. Are long term changes in sea level the same everywhere?


No. Long term changes in sea level measured at the coast (e.g. by tide gauges) are a consequence of 'real' changes in the level of the ocean (e.g. due to climate change), to which must be added changes in the level of the land.
Changes in ocean level due to climate change can be greater in some places than others because the ocean circulation will adapt to accommodate the new climate regime (see the IPCC reports for a review). Most knowledge of the global pattern of vertical land movements comes from geological data which are included in geodynamic models of the Earth. The main geological process involved is called Glacial Isostatic Adjustment (GIA). For example, in the UK, GIA results in sea level rising less rapidly in Scotland than in southern England. However, there are other geological processes, violent changes due to earthquakes being the most dramatic. Land level changes are now being investigated by geodetic research groups using the Global Positioning System and Absolute Gravity techniques. See again the PSMSL training web pages. [return to top]

14. How much does sea level rise if all the world's ice melts?


To a first approximation, if all the floating sea ice in the world melted, there would be no change in sea level at all, as the floating ice will have displaced its own weight of water. However, if land ice melts, that will raise sea level. All the world's glaciers and small ice caps contain approximately 0.5 m of sea level equivalent between them, while the great Greenland and Antarctic ice sheets contain approximately 7 and 61 m respectively. Consequently, if all the wolrd's ice melted in a very much warmer world, sea level would be approximately 70 m higher.
However, when land ice melts the distribution of the mass of water around the global ocean is by no means uniform. A large melting would result in a modification in the Earth's gravity field which would result in the sea level change being higher in some places than in others. [return to top]

Edited by taxexile, 2007-04-24 10:06:17.

[JR Texas]

dumspero, on 2007-04-24 09:57:58, said:

First, I don't think any of the posters on here have any sound idea whether the professor makes sense or not. This is especially so since these are very technical issues that are sometimes reported by people who don't understand what's being said--so they get it down wrong or take it out of context. A poster has already made this point.

Second, what's the basis to generalize to other professors or Thais, generally? That's just more of the prejudice one sees on here on a regular basis. And please, there's a big difference between criticizing something and making sweeping generalizations. The former is ok if rational, the latter is naked prejudice.

JR Texas: Thailand is a special place...so special that even the Gulf of Thailand does not respond to the laws of physics .............seriously.....maybe there was a translation problem related to another problem that I will not mention

[dumspero]

JR Texas- Have you read the posts on here? I don't know if they're right, but it makes sense to me for the reasons stated that the levels could vary. In particular, aren't the gravitational forces exerted on the planet all part of the physics to which you refer?

But if you're responding to the second part of my post--we just disagree. I don't think Thais are laughable, ridiculous or stupid and you seem to be implying (although not stating) that they are. And not just in a joking, clever way if somehow that might be ok. Up to you, but you're missing most of the wonders around you with that attitude...

[cdnvic]

I think people are getting thrown off by the variations in sea level that exist throughout the world. While these variations are a fact, they do not mean that water from melting glaciers and snow caps are all going to pile up somewhere while the rest of the world's oceans remain unchanged.

The mean sea levels of the Atlantic and pacific will continue to be different from each other, but the overall level of all seas around the world will rise accordingly as well. The differences due to density, current, and wind patterns will still be there to cause differences, but they cannot stop the volume of contiguous water that makes up the world's oceans from growing larger.

[easy_jim]

I'm a bit surprised by the simplistic responses to this Professor's claim. He may or may not be right but either way the issue is not as simple as most posters seem to think.

The sea is not level. It is pulled out of shape by a complex interaction of the magnetic pulls of the earth, the moon and the sun and the lay of the land around which the water is pulled. You cannot make broad generalisations about sea level for the whole planet.

This is why the Gulf of Thailand has a diurnal tide (only two tides a day) while the Andaman Sea has the more common semidiurnal tide (four tides a day).

[ThaiGoon]

cdnvic, on 2007-04-24 10:13:03, said:

I think people are getting thrown off by the variations in sea level that exist throughout the world. While these variations are a fact, they do not mean that water from melting glaciers and snow caps are all going to pile up somewhere while the rest of the world's oceans remain unchanged.

The mean sea levels of the Atlantic and pacific will continue to be different from each other, but the overall level of all seas around the world will rise accordingly as well. The differences due to density, current, and wind patterns will still be there to cause differences, but they cannot stop the volume of contiguous water that makes up the world's oceans from growing larger.

It would have been nice if you had cited the source of that comment as well. I was just reading very similar things especially this part "The differences due to density, current, and wind patterns" on the internet somewhere. Hmmm. (I understand you wanted to appear smart, but at least cite the source.)

[dumspero]

cdnvic- But isn't it more complicated as some posters have noted?

If there are significant reductions in the ice caps, then couldn't that affect the tilt of the earth enough to counter or exaggerate in particular areas the overall rise in the amount of sea water in the oceans? In other words, there are differences now, and isn't it possible those differences would themselves vary as opposed to just having all levels rise uniformly?

And maybe there are other variables mentioned above or not yet mentioned that would change (i.e. not just gravitational forces) if the ice caps melted quite a bit?

[meadish_sweetball]

taxexile, on 2007-04-24 10:03:34, said:

However, when land ice melts the distribution of the mass of water around the global ocean is by no means uniform. A large melting would result in a modification in the Earth's gravity field which would result in the sea level change being higher in some places than in others. [return to top]

The above quote taken from: http://www.pol.ac.uk/psmsl/puscience/ .

About PSMSL said:

Background

Since 1933, the Permanent Service for Mean Sea Level (PSMSL) has been responsible for the collection, publication, analysis and interpretation of sea level data from the global network of tide gauges. It is based in Liverpool at the Proudman Oceanographic Laboratory (POL) which is a component of the UK Natural Environment Research Council (NERC). The PSMSL is a member of the Federation of Astronomical and Geophysical Data Analysis Services (FAGS) established by the International Council for Science (ICSU). It is supported by FAGS, the Intergovernmental Oceanographic Commission (IOC) and NERC.

The more I read about it, the more it seems Khun Suphat may be on to something.

[ThaiGoon]

dumspero, on 2007-04-24 10:22:47, said:

cdnvic- But isn't it more complicated as some posters have noted?

If there are significant reductions in the ice caps, then couldn't that affect the tilt of the earth enough to counter or exaggerate in particular areas the overall rise in the amount of sea water in the oceans? In other words, there are differences now, and isn't it possible those differences would themselves vary as opposed to just having all levels rise uniformly?

True.

[Naam]

cdnvic, on 2007-04-24 10:00:23, said:

And contrary to incorrect information in the other thread on this, the Panama canal does not have locks due to the different levels of the Atlantic and Pacific (Pacific is usually 20cm higher due to prevailing winds and being slightly less dense due to salinity differences), it's because the canal actually travels over mountain lakes and it would have to be cut impossibly deep to run across Panama as a level canal. If it was the 20cm difference that was the issue a simple lock at the entrance would suffice.

correct.

[cdnvic]

dumspero, on 2007-04-24 10:22:47, said:

cdnvic- But isn't it more complicated as some posters have noted?

If there are significant reductions in the ice caps, then couldn't that affect the tilt of the earth enough to counter or exaggerate in particular areas the overall rise in the amount of sea water in the oceans? In other words, there are differences now, and isn't it possible those differences would themselves vary as opposed to just having all levels rise uniformly?

And maybe there are other variables mentioned above or not yet mentioned that would change (i.e. not just gravitational forces) if the ice caps melted quite a bit?

Well, you never know. However, it's just a wild guess. A rise in mean sea levels due to the volume of water in the world's oceans increasing is not.

[Naam]

easy_jim, on 2007-04-24 10:18:07, said:

The sea is not level. It is pulled out of shape by a complex interaction of the magnetic pulls of the earth, the moon and the sun and the lay of the land around which the water is pulled. You cannot make broad generalisations about sea level for the whole planet.

and not to forget the gravitational forces caused by earth's rotation.

[taxexile]

........ or the lowering and sinking of the earths crust due to the extra weight of the water , or the rise in land levels due to tectonic plate movement.

[PeaceBlondie]

cdnvic, on 2007-04-24 10:13:03, said:

I think people are getting thrown off by the variations in sea level that exist throughout the world. While these variations are a fact, they do not mean that water from melting glaciers and snow caps are all going to pile up somewhere while the rest of the world's oceans remain unchanged.

The mean sea levels of the Atlantic and pacific will continue to be different from each other, but the overall level of all seas around the world will rise accordingly as well. The differences due to density, current, and wind patterns will still be there to cause differences, but they cannot stop the volume of contiguous water that makes up the world's oceans from growing larger.

Now, that's a good point: if land ice melts and adds 99 trilllion square meters of volume to the overall ocean mass (I'm using rough estimates ), then the entire ocean level might rise, still leaving the existing differences in height.

I ain't no hydrologist, but surely every language and culture has a cliche such as "water seeks its own level." During Hurricane Mitch, I stood on a plot of ground that was flooding, and four local Nicaraguan men were telling my Colombian profesora how to change her plot to prevent more mudslides into her lake house. I volunteered to contact my friend who has an MS in civil engineering and is practically a hydrologist, but the natives figured it out just fine.

I don't think most of the comedians in this thread were denigrating all Thais; just this expert hydrologist. And he has a point, up to a point.

Then again, how much land ice is melting?

[John K]

Beach front property for sale Rama 4 road. Buy now before the rush!

[lannarebirth]

If there's anything to the global warming phenomenon, then thermal expansion of the oceans will contribute much more to sea levels rising than just the additional volume of water from the icecaps melting. It requires incredible computer capacity to model the possible outcome of this phenomena and it may still be wrong. The truth is no one knows exactly what may happen and where, as many of the variables may change over time.

[Dakhar]

ThaiGoon, on 2007-04-24 10:19:50, said:

cdnvic, on 2007-04-24 10:13:03, said:

I think people are getting thrown off by the variations in sea level that exist throughout the world. While these variations are a fact, they do not mean that water from melting glaciers and snow caps are all going to pile up somewhere while the rest of the world's oceans remain unchanged.

The mean sea levels of the Atlantic and pacific will continue to be different from each other, but the overall level of all seas around the world will rise accordingly as well. The differences due to density, current, and wind patterns will still be there to cause differences, but they cannot stop the volume of contiguous water that makes up the world's oceans from growing larger.

It would have been nice if you had cited the source of that comment as well. I was just reading very similar things especially this part "The differences due to density, current, and wind patterns" on the internet somewhere. Hmmm. (I understand you wanted to appear smart, but at least cite the source.)

Just plain rude. Try that mouth at a gas station in America while you are pumping gas and street justice will be administered liberally, that I promise you.

[gummy]

dumspero, on 2007-04-24 09:57:58, said:

First, I don't think any of the posters on here have any sound idea whether the professor makes sense or not. This is especially so since these are very technical issues that are sometimes reported by people who don't understand what's being said--so they get it down wrong or take it out of context. A poster has already made this point.

Second, what's the basis to generalize to other professors or Thais, generally? That's just more of the prejudice one sees on here on a regular basis. And please, there's a big difference between criticizing something and making sweeping generalizations. The former is ok if rational, the latter is naked prejudice.

I don't think the majority of the posters are being deliberate offensive to this Thai. It just so happens on this occassion that the interpretation of data by this professor has drawn certain conclusions which some of us find difficult to comprehend. In many many other situations you have differant and eminent scientists reviewing the same data and coming to totally differant conclusions, that is not to say either parties are being accused of stupidity. For example, and based on current data and evidence, you still have a very large group of people who still believe that the Americans landed on the moon in 1969 and that Princess Diana's death was an accident.