Ice Caps and Water Levels....

[iNow]

It's made pretty straight forward here. I've pulled one tiny comment from many. Folks should launch the link and read the rest for themselves.

 

http://www.realclimate.org/index.php?p=129

 

With the exception of glaciers that terminate in the ocean, and glaciers in the polar regions or at extreme high altitudes where the temperature is always below freezing, essentially just two things determine whether a glacier is advancing or retreating: how much snow falls in the winter, and how warm it is during the summer.

 

 

http://www.realclimate.org/index.php/archives/2005/05/tropical-glacier-retreat/

 

This situation here is reminiscent of the ubiquitous "Little Ice Age" problem. It is a fact of life for attribution studies that the climate changes associated with the end of the Little Ice Age overlap with the beginning of the era of industrial warming. Thus, a graph will always give the superficial impression that the present trends are just a continuation of something that began before human influences were much in the picture, leading one into the fallacy that the causes of the beginning of the trend are the same as those responsible for its continuation.

An interesting thing to watch is the effect of precipitation trends over the next decade or two. Most GCM's predict that, while some parts of the tropics get drier in response to anthropogenic greenhouse gas increases, the net tropical precipitation increases. Thus, some areas of the tropics should experience substantial increases in precipitation, which, at high elevations, will come in the form of snow. If tropical glaciers continue to retreat despite an increase in precipitation, that will constitute a powerful case for the role of air temperature.

[JohnB]

Assuming an increase in the rate of loss of 7.2% pa (doubling every 10 years) and a starting point of 220 km³ pa.

 

At the end of 100 years the rate of loss would be 225,280 km³ pa. (I'm treating this as an exponential growth rate similar to a compound interest calculation) however the total loss for the 100 years is 230,091 km³, less than 10% of the total.

 

(Edtharan, it's the rate of loss that doubles, not the total loss over time.)

 

This would mean an increase in sea levels of around 60 cm, which frankly is not much more than we get in a King Tide, however to be fair, the 40 years after that would be a mess with 60cm+ increases every year.

 

While worrying, it should be remembered that this is based on an exponential growth in loss rate and no change to weather and land use patterns and no change in any other variable. These are unreasonable assumptions so I view the estimate to be way on the high side of reality.

Well, how much area is in the glacial feeder zones and how much is outside the feeder zones? Precipitation falling outside the feeder zones will not contribute to adding to the glacier (that is obvious). So if the glacier is loosing mass, then it must be going somewhere else (outside the feeder zones).

True, but the Antarctic is a weather system unto itself. You're making assumptions as to where the water will go, can you back it up?

For the other side, and granted it is just one core, try here.

The Gomez record reveals a doubling of accumulation since the 1850s, from a decadal average of 0.49 mweq y−1 in 1855–1864 to 1.10 mweq y−1 in 1997–2006, with acceleration in recent decades.

(This one will be interesting to follow as all the other published literature I've seen puts the accretion and temp in Antarctica as pretty much stable, comments of "not statistically significant" seem common.)

 

Rerunning the exponential growth for Antartica for 100 years using a doubling every 10 years we find the total ice loss is 158,972km³ or an amazing 0.53% of the total ice mass. This figure is far less certain than the Greenland one because we really know jack sh*t about the way the weather system actually works down there.

My point is that you don't actually have to melt the ice to get the rise in sea levels. Even if the glaciers just increased their speed, putting more ice into the oceas, but not melting you would still get sea level rises.

My point is that if it doesn't melt, it clogs the channels and slows the glacier down. The reason the Greenland glaciers can accelerate is because the front is retreating meaning less friction to slow the glacier. Because of the geography of Antarctica the same conditions don't apply.

 

Further reading for this post seems to indicate problems with the estimated ice loss for Antarctica. It would appear that the majority of the loss is coming from small fast moving glaciers with small catchment basins. If so, this would preclude an indefinite doubling of the ice loss rate.

 

Also the figure would appear to apply to the coastal areas (Duh) and does not give an accurate picture of the loss/accumulation rate for the continent as a whole as the amount of deposition in the inland area is extremely uncertain.

 

Some food for thought from the IPCC Chapter 10. (10.6 to be specific)

All the models show an increase in accumulation, but there

is considerable uncertainty in its size (Table 10.6; van de Wal

et al., 2001; Huybrechts et al., 2004).

All studies for the 21st century project that antarctic SMB

changes will contribute negatively to sea level, owing to

increasing accumulation exceeding any ablation increase

(see Table 10.6).

So which one is it?

 

If you believe the ice is going to melt then you must believe the models used by the IPCC are wrong, but if you accept the models, then you have to accept the ice isn't going to melt. The two options are mutually exclusive.

 

But it's 0200 and I really, really need my beauty sleep.

 

Cheers.

[iNow]

If you believe the ice is going to melt then you must believe the models used by the IPCC are wrong, but if you accept the models, then you have to accept the ice isn't going to melt. The two options are mutually exclusive.

I think you've presented a false dichotomy, as was explained clearly by the links in my post immediately prior to yours.

 

The very "cliff's notes" summary is that the ice will melt, but there will also be increased precipitation adding new ice to the upper altitudes.

[SkepticLance]

Antarctica has an average elevation of 2500 metres, and an average precipitation of 50 mm per year.

 

http://www.antarcticconnection.com/antarctic/weather/snow-ice.shtml

 

With an area of 14 million sq kms, this means a total ADDITION of snow and ice each year of 700 billion tonnes of water weight. You need to take this into account in your sums also.

 

Since most of that falls at substantial altitude, where the temperature never gets anywhere near melting point, it is gonna stay there, except as moving ice in glaciers.

 

With global warming, as the sea warms up, more moisture enters the air, which means more will fall as snow and ice. The 700 billion tonnes will only increase.

[iNow]

Since most of that falls at substantial altitude, where the temperature never gets anywhere near melting point, it is gonna stay there, except as moving ice in glaciers.

 

At what altitude will this precipitation fall? What percentage of the precipitation will land at high altitudes, and what percentage will not? What is the average temperature at those altitudes? Inquiring minds want to know.

[SkepticLance]

Since the average altitude in Antarctica is 2500 metres, we can assume that relatively little is below,say, 1000 metres. Since most of the time, the temperature is below zero even at sea level, it is reasonable to conclude that most of the precipitation will fall at an altitude that stays well below zero.

 

In fact, the bulk of Antarctica has not been warming. Certain global warming distorters of truth will say that west Antarctica has been warming rapidly, implying half the continent, and thereby trying to lead people into a false belief. What they do not tell you is that west Antarctica is mostly the Antarctic Peninsular, and accounts for a relatively tiny part of that continent. The vast bulk of the continent is actually cooling, albeit very slowly.

[iNow]

Since the average altitude in Antarctica is 2500 metres, we can assume that...

Just so you know, it was exactly where I ended your quote above that I stopped reading.

[SkepticLance]

I am pleased to hear that, iNow.

 

Now that you have left, the adults can continue their conversation.

[JohnB]

I think you've presented a false dichotomy, as was explained clearly by the links in my post immediately prior to yours.

 

The very "cliff's notes" summary is that the ice will melt, but there will also be increased precipitation adding new ice to the upper altitudes.

Sorry mate, your post was made while I was writing mine so I didn't see the links before posting.

 

However, the two links refer to mid latitude glaciers, not the Antarctic. My contention (and the opinion of the IPCC) is that the Antarctic Ice Sheet won't melt.

 

So it's not a false dichotomy. According to the IPCC models the Antarctic ice won't melt and may increase in mass due to increased precipitation. So if you believe the ice will melt, then you must believe the models are flawed. If you believe the models are robust, then you can't believe the ice will melt.

 

You can't have it both ways.

 

(Sorry to appear dense, but I've read both links, what the hell are "cliff's notes"?)

[jryan]

"Cliff's Notes" is a line of books sold here in the U.S. that are outlines of famous books that cover just what is important to take from the original text. It has been used for years by high school and college kids who are bound and determined to graduate without actually being educated.

[swansont]

Sorry mate, your post was made while I was writing mine so I didn't see the links before posting.

 

However, the two links refer to mid latitude glaciers, not the Antarctic. My contention (and the opinion of the IPCC) is that the Antarctic Ice Sheet won't melt.

 

So it's not a false dichotomy. According to the IPCC models the Antarctic ice won't melt and may increase in mass due to increased precipitation. So if you believe the ice will melt, then you must believe the models are flawed. If you believe the models are robust, then you can't believe the ice will melt.

 

You can't have it both ways.

 

Sure you can. You can have melt, but precipitation that exceeds the amount of melting.

[iNow]

I am pleased to hear that, iNow.

 

Now that you have left, the adults can continue their conversation.

 

I believe you've quite missed my point, sir. I asked specific questions with the intention of reviewing specific sources and claims, to which you decided to reply using unfounded speculation and unsupported premises. There's really no need to engage in the ad hominem attack suggesting that I am not an adult. I apologize that you dislike the nature of my challenges to your position, but the challenges are quite valid all the same.

 

It appears again that you've presented a position which you are not able to support.

[JohnB]

Sure you can. You can have melt, but precipitation that exceeds the amount of melting.

I think there is a communication problem here.

 

By saying "melting the Antarctic ice cap", or words to that effect, I assumed we were referring to the concept of it, you know, melting, disappearing?

 

Again, my contention is that this will not happen, which for a wonder agrees with the IPCC.

 

Phrase it another way. "Antarctica will be ice free within 400 years" True or false?

 

I say false.

 

"Cliff's Notes" is a line of books sold here in the U.S. that are outlines of famous books that cover just what is important to take from the original text. It has been used for years by high school and college kids who are bound and determined to graduate without actually being educated.

Thanks.

 

SL, inow has a point. We shouldn't assume values. inow, I hope you will accept accepted approximations as the weather station network is a little on the sparse side down there.

[swansont]

I think there is a communication problem here.

 

By saying "melting the Antarctic ice cap", or words to that effect, I assumed we were referring to the concept of it, you know, melting, disappearing?

 

Again, my contention is that this will not happen, which for a wonder agrees with the IPCC.

 

I don't see any posts here that contended that the Antarctic ice cap would disappear. But you have to look at losses and gains, because the contention that SkepticLance made

 

Antarctica has an average elevation of 2500 metres, and an average precipitation of 50 mm per year.

 

http://www.antarcticconnection.com/antarctic/weather/snow-ice.shtml

 

With an area of 14 million sq kms, this means a total ADDITION of snow and ice each year of 700 billion tonnes of water weight. You need to take this into account in your sums also.

 

Since most of that falls at substantial altitude, where the temperature never gets anywhere near melting point, it is gonna stay there, except as moving ice in glaciers.

 

With global warming, as the sea warms up, more moisture enters the air, which means more will fall as snow and ice. The 700 billion tonnes will only increase.

 

assumes no losses whatsoever. So it would appear that "melting" vs "no melting" was indeed being interpreted differently in two separate ways.

[SkepticLance]

To iNow

 

Logic is an acceptable means of argument. You cannot reject an argument on the basis that it is logic. I suggested that, with an average altitude of 2500 metres, most of Antarctica will be over 1000 metres. This is logic and is, in fact, correct.

http://www.enotes.com/earth-science/antarctica

 

I quote :

 

"Almost all of Antarctica is under ice, in some areas by as much as 2 mi (3 km). The ice has an average thickness of about 6,600 ft (2,000 m), which is higher than many mountains in warmer countries. This grand accumulation of ice makes Antarctica the highest continent on Earth, with an average elevation of 7,500 ft (2,286 m)."

 

I find it very exasperating, iNow, how when you disagree with a point I make, you try to deny the facts behind my point. That is a serious flaw in a person who considers himself to be a scientific thinker. Good scientists respect data, and only deny the data if there is good reason to do so. You try to deny data only because you don't like it, and that is just plain annoying.

 

On this last occasion, for example, when I said that most of Antarctica was over 1000 metres, you had absolutely no reason to go into denial except your own emotional reaction to a point you disagreed with. That is not the tactic of an adult.

 

This is not an ad hominem attack. I am not criticising you. I am criticising your tactics.

 

I am asking you to, please, stop attacking data and logic unless you actually have reason to believe it might be wrong.

[swansont]

To iNow

 

Logic is an acceptable means of argument. You cannot reject an argument on the basis that it is logic. I suggested that, with an average altitude of 2500 metres, most of Antarctica will be over 1000 metres. This is logic and is, in fact, correct.

http://www.enotes.com/earth-science/antarctica

 

I quote :

 

"Almost all of Antarctica is under ice, in some areas by as much as 2 mi (3 km). The ice has an average thickness of about 6,600 ft (2,000 m), which is higher than many mountains in warmer countries. This grand accumulation of ice makes Antarctica the highest continent on Earth, with an average elevation of 7,500 ft (2,286 m)."

 

I find it very exasperating, iNow, how when you disagree with a point I make, you try to deny the facts behind my point. That is a serious flaw in a person who considers himself to be a scientific thinker. Good scientists respect data, and only deny the data if there is good reason to do so. You try to deny data only because you don't like it, and that is just plain annoying.

 

On this last occasion, for example, when I said that most of Antarctica was over 1000 metres, you had absolutely no reason to go into denial except your own emotional reaction to a point you disagreed with. That is not the tactic of an adult.

 

This is not an ad hominem attack. I am not criticising you. I am criticising your tactics.

 

I am asking you to, please, stop attacking data and logic unless you actually have reason to believe it might be wrong.

 

It's not actually data, or a fact, if you assume it. Which is what you did.

 

If you had provided a link the first time around, for this and the other claim*, (for which, in general, you have been asked repeatedly to do) it might have short-circuited this whole exchange. And I find both the lack of citation and the sniping annoying.

 

You could have provided a link like this, which actually shows the elevation. Your earlier post on precipitation, where you cited the 2" average, but not the distribution, would have tied in well with that map:

 

"most of the snow falls within 120 to 190 miles of the coast. Average precipitation on the coast is 20 to 50 inches of snow (7 to 16 inches of water equivalent). The Antarctic Peninsula has highest precipitation of the continent, (36 inches water equivalent)."

 

Given that, iNow's questions about the distribution don't seem out of line — they point to the fact that you weren't citing the most relevant data. Much of the precipitation indeed falls where the elevation is actually below 2000 m.

 

——

*to wit: "In fact, the bulk of Antarctica has not been warming" Find me a link.

 

 

 

———

And let me add this: while iNow has occasionally stepped across the line in these discussions, I think that in this thread that has not been the case. All that has occurred is a request to give some supporting documentation, i.e. not accepting an assumption when one could cite something far more solid. Which would seem to be perfectly acceptable to a skeptic.

 

I would suggest you not lecture anyone about the quality of their scientific thinking and instead lead by example.

[SkepticLance]

Swansont

 

If this had been the only case, you would be right. However, it is not. iNow repeatedly denies data and logic. For example : in the pit bull thread, we have official statistics showing human deaths from dog attack are 37% pit bull. iNow refuses to accept that as data and repeatedly tries to say the officials who compiled that data are incompetent. The denial of data is his standard rebuttal when someone presents data he does not like.

 

In this case, I presented a point as logic - not data. However, iNow preferred not to accept my logic though you admit I was right. Again, if it happened once, then fine. However, it is repeatedly the case. My own view is that iNow has a real problem admitting he can be wrong, and reverts to inappropriate denials of data or logic to avoid having to make that admission.

 

If he was able to show that my logic was faulty - then fine. However, he could not. Again, the constant reversion to denial is not good scientific thinking.

 

Swansont, you said

 

"If you had provided a link the first time around, for this and the other claim*, (for which, in general, you have been asked repeatedly to do) it might have short-circuited this whole exchange. And I find both the lack of citation and the sniping annoying."

 

I was making a point of logic, and I gave a sufficient citation to support that logic. If I had presented it as fact, I would have needed another citation. You are being unreasonable to demand 'proof' of a point of logic.

 

If I say, given that 'A' is true, then 'B' follows - that is logic. In that kind of argument, I do not need to supply a citation proving 'B'. Just the citation proving 'A', which I did.

 

I find it a bit depressing to see someone as smart and educated as you supporting irrational illogic based on denial of data and denial of logic.

[swansont]

Swansont

 

If this had been the only case, you would be right. However, it is not. iNow repeatedly denies data and logic. For example : in the pit bull thread, we have official statistics showing human deaths from dog attack are 37% pit bull. iNow refuses to accept that as data and repeatedly tries to say the officials who compiled that data are incompetent. The denial of data is his standard rebuttal when someone presents data he does not like.

 

I'm talking about this thread. The pit bull thread, in which I have not participated nor have I read, is irrelevant to this discussion.

 

In this case, I presented a point as logic - not data. However, iNow preferred not to accept my logic though you admit I was right. Again, if it happened once, then fine. However, it is repeatedly the case. My own view is that iNow has a real problem admitting he can be wrong, and reverts to inappropriate denials of data or logic to avoid having to make that admission.

 

If he was able to show that my logic was faulty - then fine. However, he could not. Again, the constant reversion to denial is not good scientific thinking.

 

You admit you presented a point as logic, not data, yet you complain of denial of facts and not respecting data. You can't have it both ways. And the underlying points are that this is a matter of facts and data, and I didn't admit that you were right —

 

The clarification for which iNow asked is:

 

At what altitude will this precipitation fall? What percentage of the precipitation will land at high altitudes, and what percentage will not? What is the average temperature at those altitudes? Inquiring minds want to know.

 

and the correct answer is that the highest levels of precipitation fall at the lower altitudes, near the coast (from your link) and this is not the answer you gave.

 

Swansont, you said

 

"If you had provided a link the first time around, for this and the other claim*, (for which, in general, you have been asked repeatedly to do) it might have short-circuited this whole exchange. And I find both the lack of citation and the sniping annoying."

 

I was making a point of logic, and I gave a sufficient citation to support that logic. If I had presented it as fact, I would have needed another citation. You are being unreasonable to demand 'proof' of a point of logic.

 

If I say, given that 'A' is true, then 'B' follows - that is logic. In that kind of argument, I do not need to supply a citation proving 'B'. Just the citation proving 'A', which I did.

 

This isn't about whether your deduction of the altitude of Antarctica is correct. The question at hand was given above — where is the precipitation highest.

 

I find it a bit depressing to see someone as smart and educated as you supporting irrational illogic based on denial of data and denial of logic.

 

Do you really think that attacking me is the wisest course of action here?

[SkepticLance]

Swansont

 

You are talking around the issue. I have no doubt your facts are correct. However, the point is that the continental body of Antarctica is at a temperature that ensures that precipitation is frozen. Very little is close to sea level, and it is bloody cold!

 

This means that the 700 billion tonnes I spoke of falls as snow and ice - not rain, and remains for very substantial periods on land. Any water stored on land is acting contrary to rising sea levels. The fact that continental Antarctica, as opposed to the Antarctic Peninsular, has cooled rather than warmed indicates that there is no danger that the masses of snow and ice are likely to contribute to rising sea levels any time soon.

 

As you know, I am sceptical of the catastrophist interpretation of global warming. Those who claim that the water stored on Antarctica will mostly melt and flood the world are talking garbage.

 

And my deduction that most of Antarctica is above 1000 metres remains correct, whatever the nay sayers might claim.

[Edtharan]

This means that the 700 billion tonnes I spoke of falls as snow and ice - not rain, and remains for very substantial periods on land. Any water stored on land is acting contrary to rising sea levels. The fact that continental Antarctica, as opposed to the Antarctic Peninsular, has cooled rather than warmed indicates that there is no danger that the masses of snow and ice are likely to contribute to rising sea levels any time soon.

Ok lets look at this:

 

1)

"most of the snow falls within 120 to 190 miles of the coast. Average precipitation on the coast is 20 to 50 inches of snow (7 to 16 inches of water equivalent)."

 

2) Once it has fallen as snow it can't move up hill (towards the centre of the continent).

 

At 20 to 50 inches per year, this give aproximately 3 to 16 feet of growth each year. Well use the lowest value (the snow will compact and I am being conservitive).

 

At 3 feet per year, over 100 years this is 300 fett increase in ice levels due to priciptitation. However, we are not seeing the edges of antactica grow upwards at this speed. In fact they seem to be about the same height.

 

So then, according to point (2), as the snaow that has fallen on the edges of antarctia can't be moving inland, they must be moving outwards and that way lies the ocean.

 

This all means that although the edges might be getting around 3 fett of snow each year, it also means around 3 feet of snow are being moved into the oceans.

 

This is an equilibrium. The amount of snow being deposited is (roughtly) the same as the amount of snow being moved away (into the oceans). Increasing the rate at which this moves, by a small amount of warming, will tip this equilibrium. The result of which is that the amount of ice in Antactia is reduced and an increase in the amout of water in the atmosphere which contribute to further warming, or in the oceans which contributes to riseing sea levels.

 

And the most important thing here is that the temperatures do not have to exceed the melting point of ice/water . In fact you don't even need to increase temperatures at all. Just a chang in the amount of precipitation will do this.

 

Make a region colder and the water in the atmosphere will be dumped else where. Change the pattern of wind currents and the water in the atmosphere is moved and dumped else where.

 

Global warming is not just about temperature increases. There will be regions where the temperatures will lower and even places where they remain the same. Global Warming is badly named. It is a hang over from when they didn't really understand the full complexity of what retaining extra energy in the atmosphereic/oceanic systems would do, they though it would just lead to increased temperatures. Climate Change is a much better name, but still not perfect.

 

The fact that continental Antarctica, as opposed to the Antarctic Peninsular, has cooled rather than warmed indicates that there is no danger that the masses of snow and ice are likely to contribute to rising sea levels any time soon.

No. This indicates a change in the atmosphereic systems around Antactica. This means that patterns of prcipititation will change. This also means a lot of consiquences that we don't yet know. Just because Antactica is getting colder does not mean that we won't loose ice from it. If these changes mean that less precipitation falls, then there will be less ice build up and with ice removal increasing (faster moving glaciers), then ice will disappear from Antactica without it melting.

 

Let me state this again for you: Melting is only one way for ice to be removed from Antactica.

 

It is the ballance of ice that is being added by precipitation and the removal of ice through all the other means that keeps the ice locked up in Antactica. Shift the ballance away from addition to removal (by reduceing pricipitation, or increasing glacial flow), then you will loose ice from Antactia.

 

You seem to be hung up on ice melting into water. This is just one of many ways that you can reduce the ice covering Antactica.

[LookUp2]

Ok lets look at this:

 

1)

 

2) Once it has fallen as snow it can't move up hill (towards the centre of the continent).

 

At 20 to 50 inches per year, this give aproximately 3 to 16 feet of growth each year. Well use the lowest value (the snow will compact and I am being conservitive).

 

At 3 feet per year, over 100 years this is 300 fett increase in ice levels due to priciptitation. However, we are not seeing the edges of antactica grow upwards at this speed. In fact they seem to be about the same height.

 

So then, according to point (2), as the snaow that has fallen on the edges of antarctia can't be moving inland, they must be moving outwards and that way lies the ocean.

 

This all means that although the edges might be getting around 3 fett of snow each year, it also means around 3 feet of snow are being moved into the oceans.

 

3 feet of snow = approx 3 inches of water when melted. Theres alot of air in snow. Also snow evaporates some even when temps are very cold.

 

I havent read the whole article but has more details here:

http://bgs.ucalgary.ca/files/bgs/valeo_skone_ho_poon_srestha_2005.pdf

[JohnB]

So it would appear that "melting" vs "no melting" was indeed being interpreted differently in two separate ways.

I think so. I was working from the comment in the OP;

Everyone seems to say, "when the ice caps melt, the water levels will rise, flooding us all."

It was this contention I was arguing against.

 

Perhaps it would be clearer if we were to say that the ice mass will increase or decrease?

2) Once it has fallen as snow it can't move up hill (towards the centre of the continent).

Wanna bet? You are talking about the continent with the highest winds on the planet. There is a lot more than 50mm/year of snow at the pole. A C 130 crashed back in the 70s and was moved to be a runway marker on January 7, 1975. By 2002 about 1 foot of the tail was all that was above the surface. Website with photos here.

As an aside, it looks like the people down there have made their own traditions with the "Winterovers" creating a new South Pole marker each year. I think the 2007 version is very attractive.

This is an equilibrium. The amount of snow being deposited is (roughtly) the same as the amount of snow being moved away (into the oceans). Increasing the rate at which this moves, by a small amount of warming, will tip this equilibrium. The result of which is that the amount of ice in Antactia is reduced and an increase in the amout of water in the atmosphere which contribute to further warming, or in the oceans which contributes to riseing sea levels.

This is not what the projections say. While the rate of loss due to melting or other means will increase, so will the rate of deposition. Therefore the total ice mass of Antarctica will increase and will not contribute to a rise in sea levels.

 

Edtharan, I've reviewed the thread and so far you have not provided a single link to back up what you contend. Would you care to provide some evidence to back your contention that the ice mass of Antarctica will decrease or are you going to continue hand waving? (Please don't take this personally. It's the first time ever I've had the opportunity to accuse someone of "hand waving" and I'm going to milk it for all it's worth.)

 

SL, knock off the comments about Swansont. It is not part of his role here to moderate threads and ensure they stay civil. Personally I appreciate his input as he makes me find proof for what I assume to be correct. Treat his comments as a way to better your debating technique, I do.

[swansont]

Swansont

 

You are talking around the issue. I have no doubt your facts are correct. However, the point is that the continental body of Antarctica is at a temperature that ensures that precipitation is frozen. Very little is close to sea level, and it is bloody cold!

 

I don't see where anyone has challenged that point.

 

This means that the 700 billion tonnes I spoke of falls as snow and ice - not rain, and remains for very substantial periods on land. Any water stored on land is acting contrary to rising sea levels. The fact that continental Antarctica, as opposed to the Antarctic Peninsular, has cooled rather than warmed indicates that there is no danger that the masses of snow and ice are likely to contribute to rising sea levels any time soon.

 

But the 700 billion tons is not the net addition, because you haven't determined the losses.

 

As you know, I am sceptical of the catastrophist interpretation of global warming. Those who claim that the water stored on Antarctica will mostly melt and flood the world are talking garbage.

 

Non sequitur. Where has that claim been brought up in this thread? The OP offered it as a premise, not a prediction, in the context of understanding why water levels would rise should the ice melt. Most of the rest of the thread has been correcting points of math and physics.

 

And my deduction that most of Antarctica is above 1000 metres remains correct, whatever the nay sayers might claim.

 

And that was never really a point of contention.

 

I think so. I was working from the comment in the OP;

 

It was this contention I was arguing against.

 

Perhaps it would be clearer if we were to say that the ice mass will increase or decrease?

 

And I (and I assume others) were proceeding from this point assuming ice had melted, and not discussing the merit of the premise. So yes, I think there has been a little difference interpretation in what was meant by "melting."

 

It is not part of his role here to moderate threads and ensure they stay civil.

 

I think you have an extraneous "not" in there.

[JohnB]

I think you have an extraneous "not" in there.

Oh? Okay. I kind of like the "inthread" moderation style then. It improves the debate more than deleting a post or a curt "Knock it off" would.

 

Cheers.

[Edtharan]

Edtharan, I've reviewed the thread and so far you have not provided a single link to back up what you contend. Would you care to provide some evidence to back your contention that the ice mass of Antarctica will decrease or are you going to continue hand waving? (Please don't take this personally. It's the first time ever I've had the opportunity to accuse someone of "hand waving" and I'm going to milk it for all it's worth.)

No offense taken. I haven't provided any links to data as I have not been providing any data. I have just been using the data other have provided and working out conclusions based on that. So the only "links" I can rally provide are to other people's posts (which I do when I quote them ).

 

For example when we were talking about rate ice loss I used the data provided by others and then just did the calculations (admittedly simplified and conservative) to show what would occur. I didn't actually present the data of the ice loss rate, just used what others had provided.

 

Wanna bet? You are talking about the continent with the highest winds on the planet.

Ok, yes, wind can blow ice up hill, but it can also blow it down hill too. It can make a differecne, but I am not sure how big of one it is. I would guess that the rate of snow beling blown up would roughly equal the amount being blown down (or at some point an equilibrium would be reached - like once all the places where snow could lodge have been filled the wind would just sweep the snow over the rises). I would imagine it would be a bit like sand in a desert.

 

When wind blows sand (or snow) it will pile up in drifts where something slows the wind down (like a crack in a rock - or a crashed C 130) enough that the weight of the particulates carried by it are too heavy for the wind to shift. These drifts then cause the wind to slow down and so on as a feedback loop develops. This causes the build up of particles (sand or ice) and it creates mounds that can easily cover very large objects (towns included). This is not indicitive of a wide scale increase in the particulates, but it is a strictly local phenomina.

 

Without further knowledge of the surounding areas, this example does not prove your point (but neither can it be used to disprove it either). It is essentially a read herring (logical falacy) as it detract from what we are discussing. Unless you can show that this increase in height is a wide spread increase (on the scale of kilometres rather than a few hundred meters) then this proves nothing and does not contibute at all to the discussion.

 

It is a bit like me sticking my head out the window and seeing that it is raining here at the moment and then concluding that it must be raining over the whole country at the moment.

 

Also, the site of a landing strip would have been chosen for its stability. This means very little movment of ice. So a build up would be expected in this scenario as ice and snow would be accumulating (falling as prcipitation or being blown there) and very littel would be moving away from that area. Too much movement would create cravases and otehr hazardous concerns. So not only can the build up if snow over the C 130 be (partially) attributed to the fact that it acts like a wind break, you also have the other local phenomina that is the site would have been selected for its lack of movment of ice.

 

This is good example of why the plural of "Anectode" is not "Evidence".