Global Warming: (Green)Peace on You

[Xerxes]

Absolutely fascinating story regarding global warming - apparantly large quantities of ice have been melting *before* the invention of CFC's and SUV's. Gee whilikers, global warming in the 1900's? How is this possible...

Story (http://www.dailytelegraph.co.uk/news/main.jhtml;$sessionid$WFPW5DHNFW5OBQFIQMFCFF4AVCBQYIV0?xml=/news/2002/08/17/wglac17.xml&sSheet=/news/2002/08/17/ixworld.html&_requestid=33285&_requestid=121335&_requestid=396269&_requestid=506625)

[Lapikas]

It's carbonocside (hmm.. not sure this is the word I'm thinking. God damn my bad english) that makes the atmosphere warmer. So volcanoes release it also. Atleast I think I read that somewhere..

[Xerxes]

Carbon Dioxide.... (Co2)?

[Lapikas]

Yes. That's the shit.. But I'm not so sure about this..

[Xerxes]

Not to be confused with Chloroflourocarbons.... of course.

[Lapikas]

Well duh.. of course not :D

[fwgx]

Large chunks of ice falling into the sea doesn't affect water levels at all. The ammount of ice in the wate is the same when frozen as when liquid (water expands when frozen remember). It's the fact that when the water warms up it gets bigger. So all the pictures you see of massive chunks of ice falling into the sea aren't affecting the sea level much at all.

[Lapikas]

Um.. But that piece of ice that drops to water, wasn't there before.. So doesn't that really increase the quantity of water?

[fwgx]

Well if a bit fell off the top then yes but if a piece just breaks away from the rest, then no.

[whiteflip]

the industrial age started in 1890
back then they had instrumentation capable to record data that the globe was in fact warming. word was less wide spread then

earth goes through warming and cooling periods. lushes lands suddenly turning to VAST deserts? climate changes and climate changes are caused by global warming

global warming is could be caused
earths isocolating tilt maybe
soloar flare ups that lasts centuries?
elnino
humans making gases.....
aliens teraforming our planet.

the thing that ticks me off are people deny globabl warming exist. i like how bush says that global warming does exist unlike other republicans and hes right. we cant reverse 100 years of damage over night. so the best we can do is limit damage and work on a means to vast deploy a solution across the sky.... limiting works for me

[whiteflip]

from what i heard alskan ice berg chuncks contain eight times more ice than normal ice. this is because it gets compacted under its own weight. what i dont understand is why this much heavy version of ice floats when it breaks off....

(maybe the icebergs are bottom heavy. heavy part on bottom light part on top.)

[Lapikas]

Originally posted by whiteflip
humans making gases.....
aliens teraforming our planet.
Yeah! Humans indeed makes gases :D Hey stop that! You stink!

And of course there has to be that conspiracy thing.

[c2R]

Originally posted by Phily Baby
Well if a bit fell off the top then yes but if a piece just breaks away from the rest, then no.

No, that's not correct - Try it with ice cubes in cup - I guarantee you that it doesn't matter how much ice you put into the cup, when it melts there will be no net difference in water level. This is because ice on top of other ice just forces more ice underneath the water level. If some ice falls off the top and into the water and melts, this decreases the amount of ice below water level...

BUT the South Pole, of course is land covered with ice - so when this melts the sea level will rise. However, the amount of ice is not really significant, so we don't need to worry about that. As you said, it's more significant that water itself takes up more space as temperature rises - which is the cause of the sea level rise.

[fwgx]

Oh yeah of course. Me being silly I forgot that it would make the main iceberg as a whole smaller :o

[. - .... .- -. ....]

Originally posted by Phily Baby
Large chunks of ice falling into the sea doesn't affect water levels at all. The ammount of ice in the wate is the same when frozen as when liquid (water expands when frozen remember). It's the fact that when the water warms up it gets bigger. So all the pictures you see of massive chunks of ice falling into the sea aren't affecting the sea level much at all.

er... not quite. Ice has a lower density than water (about 5/7, if I remember correctly), and therefore floats. That means that a large proportion of the ice is above the level of the water. This means that when it melts, this additional volume is added to the volume of the water already there.

Also, you have to bear in mind that ice sheets cover land masses, and therefore have no effect on the sea level until they melt and icebergs break off and fall into the ocean. This can cause more icebergs to form by weakening the glaciers, causing more cracks and making ice more likely to break off. As soon as the ice falls into the ocean, the ocean rises a little.

The main ice covered landmass is Antarctica at the South Pole, with about 90 percent of the world's ice (and 70 percent of its fresh water). Antarctica is covered with ice an average of 2,133 meters (7,000 feet) thick. If all of the Antarctic ice melted, sea levels around the world would rise about 61 meters (200 feet).

[fwgx]

The submersed part of an iceberg is the same volume as the whole mass of the iceberg in a water state.







/\

/ \

----/----\------

/ \

/________\





So that the part below the dashed line is the same size as the whole triangle of ice when liquid. If that makes sence. So whether the water is liquid or ice it still takes up the same ammount of space so it wont affect the sea levels. What does affect the levels is the warming of the water, which makes the water bigger but obviously doen't displace this extra size outside the water like ice does.

[. - .... .- -. ....]

Would it ever occur to you that the ice in question could be sitting on a great big rock? The entire continent of Antartica for example. In which case it would never be submerged in the ocean unless it melted. Also taking into account that most ice shelves rest on the sea bed for many miles out to sea, and therefore never displace their own volume in water.

The problem here is not icebergs - they are just a speck of dust in the bigger scheme of things. The problem lies within the icecaps. If the entire north pole (which floats in the water and also where the ice is not nearly as thick) melted, it would have negligible effect on the worlds ocean levels. however, if the same thing occured at the south pole, sea levels would rise by 200 feet, as calculated above.

[fwgx]

I was going on floating ice like that shown on the news we see that clearly isn't big enough to be resting on the sea bed, and which floats out to sea.

[Scar Da Kookee]

Originally posted by whiteflip
humans making gases.....
aliens teraforming our planet.


aw, great another WinDude on our hands... :rolleyes:

[Bop]

For once I think Windude might be right...

[. - .... .- -. ....]

Originally posted by Phily Baby
I was going on floating ice like that shown on the news we see that clearly isn't big enough to be resting on the sea bed, and which floats out to sea.

And that ice has to come from somewhere. It's falling from the icecaps as they are being warmed, thus contributing to the volume of water in the oceans.

[patroclus22]

I've learned to take anything Greenpeace says with a grain (and possibly a 5 lb bag) of salt. They have a tendency to jump into hysterics about every environmental issue, and use unorthodox--and often illegal--methods to bring them to people's attention.
Quite frankly, I just don't trust them. As Xerxes once pointed out, environmentalists are more often than not anti-capitalists hiding behind environmentalism.

[Mizter_E]

THe earth is leaving its Ice-Age phase.. nothing to worry about..

[c2R]

Originally posted by ethan_h


And that ice has to come from somewhere. It's falling from the icecaps as they are being warmed, thus contributing to the volume of water in the oceans.

That's not quite true - as myself and Phily were trying to explain.

The north pole can be modeled as one really big iceberg - it's literally a large mass of ice floating at the top of the world. Therefore if it melts there is no net change in sea level.

Much of the South Pole is the same (all the large ice shelves are floating on the water). Of course there is alot of land covered in snow and ice too, but the effect of this melting is negligable - it'd only cause sea levels to rise by a few centimeters at most.

The real problem is the actual water, which expands when it gets hot.

[. - .... .- -. ....]

Originally posted by c2R


That's not quite true - as myself and Phily were trying to explain.

The north pole can be modeled as one really big iceberg - it's literally a large mass of ice floating at the top of the world. Therefore if it melts there is no net change in sea level.

Which is prety much what I said above....

"If the entire north pole (which floats in the water and also where the ice is not nearly as thick) melted, it would have negligible effect on the worlds ocean levels. "

Much of the South Pole is the same (all the large ice shelves are floating on the water). Of course there is alot of land covered in snow and ice too, but the effect of this melting is negligable - it'd only cause sea levels to rise by a few centimeters at most.

Not true - not by a long shot.

http://wuzwuz.nuigalway.ie/~mike/winamp/proof.jpg

Slightly higher than your "few centimetres", wouldn't you think?? ;)

[c2R]

Originally posted by ethan_h


Not true - not by a long shot.

http://wuzwuz.nuigalway.ie/~mike/winamp/proof.jpg

Slightly higher than your "few centimetres", wouldn't you think?? ;)

OK, I'll concede that one!

After looking at some of my old university notes, the rise in sea levels that we calculated by the melting of all ice on the south pole would be a few meters (like about 35), not centimeters.

This disagrees slightly with your proof (you've got a figure of around 65m I think, though I'm not quite sure on the conversion from feet to metric) because yours assumes all the ice is on land (which is not true - there are significant dense ice deposits in the Ross Sea and Weddell Sea, as well as around most of the edges of the land).

Having said this 35m is still alot...

[deadrabbit]

whiteflip-
i like how bush says that global warming does exist unlike other republicans and hes right.
he's finally acknowledged that there is a problem, but still has no interest in fixing in. remember, he was the one that pulled the US out of the kyoto summit (or was it conference?).

[J. Burnaway]

Just my two cents on floating icebergs only:
Things that float displace their weight in water. If you took the volume of a ship that is below the waterline, and multiply it by the density of sea water, you will find that the number you calculate is exactly the same as the entire weight of the ship. Since icebergs are all water, and are less dense than water, there is a part of the icberg above the waterline, since the total volume of the iceberg is greater than its weight divided by the density of the seawater. Once the iceberg melts, it becomes more dense, and exactly fills the underwater space of the iceberg, and it doesn't raise the seawater one bit.

Switching topics, I have heard (don't remember where) that the earth is actually due for another ice age, and that global warming might be counteracting the cooling effect we should be experiencing, or might be experiencing in the not too distant future. Has anyone else heard this?

[c2R]

Originally posted by J. Burnaway
Switching topics, I have heard (don't remember where) that the earth is actually due for another ice age, and that global warming might be counteracting the cooling effect we should be experiencing, or might be experiencing in the not too distant future. Has anyone else heard this?

Yes, the theory goes that the reason for the global temperature rise is that there's a cycle of "ice ages", and we're right between two at the moment. Thus, the theory says, some time in the not-too-distant future temperatures will begin to slowly fall...

It's a quite plausible theory - judging by temperature charts we are in the middle between two ice ages.

However, different charts show a positive correlation between CO2 emissions and global temperatures.

You can prove anything with statistics.

[eleet-2k2]

Originally posted by c2R


OK, I'll concede that one!

After looking at some of my old university notes, the rise in sea levels that we calculated by the melting of all ice on the south pole would be a few meters (like about 35), not centimeters.

This disagrees slightly with your proof (you've got a figure of around 65m I think, though I'm not quite sure on the conversion from feet to metric) because yours assumes all the ice is on land (which is not true - there are significant dense ice deposits in the Ross Sea and Weddell Sea, as well as around most of the edges of the land).

Having said this 35m is still alot... That math pic brought to mind an old episode of Pinky and the Brain where they melted the polar ice caps and it flooded the world up to the 30th floor. Well, if the average floor is ~9 feet for normal business buildings, we may assume that:

223 / 9 = 24.777
= ~25 floors

Thus we lose all land below the 25th floor. Not a bad assumption (or calculation) for just a kid's TV show. ;)


Oh and Xerx - Carbon Dioxide = CO2 not Co2 ;) molecule of 2 Cobalt atoms. :p ;)

[Neko]

theres a saying,

Red sky at night, Shepards delight
Sheep drown in morning, Global warming

[Sandman2012]

Originally posted by c2R
You can prove anything with statistics.

14% of all people know that.

[Neko]

the western continent reminds me alot of a fridge freezer, america being the fridge, and canada being the freezer at the top.

no point to that really, just that it almost means most of the fruits are stored in the fridge, and the cool produce is stored in the freezer ;)

yey for another anti american observation ;)
-dodges rotting fruit that comes, if i'm not mistaken, from the fridge of all places ;)

[. - .... .- -. ....]

Originally posted by c2R


OK, I'll concede that one!

After looking at some of my old university notes, the rise in sea levels that we calculated by the melting of all ice on the south pole would be a few meters (like about 35), not centimeters.

This disagrees slightly with your proof (you've got a figure of around 65m I think, though I'm not quite sure on the conversion from feet to metric) because yours assumes all the ice is on land (which is not true - there are significant dense ice deposits in the Ross Sea and Weddell Sea, as well as around most of the edges of the land).

Having said this 35m is still alot...

I'm not finished yet!! ;) :p

If you do a quick google search, I think that you will find that the textbook value lies somewhere around 200-250 feet, which is pretty close to what I calculated.

[J. Burnaway]

Originally posted by Neko
the western continent reminds me alot of a fridge freezer, america being the fridge, and canada being the freezer at the top.

no point to that really, just that it almost means most of the fruits are stored in the fridge, and the cool produce is stored in the freezer ;)

yey for another anti american observation ;)
-dodges rotting fruit that comes, if i'm not mistaken, from the fridge of all places ;)
If you can prove anything with statistics, you can insult anyone by using really lame analogies.

[Xerxes]

Originally posted by Neko

yey for another anti american observation ;)
-dodges rotting fruit that comes, if i'm not mistaken, from the fridge of all places ;)

And I once heard North America compared to an apartment building- Canada being a loft right above a really great party below;)

[Xerxes]

Originally posted by deadrabbit
whiteflip-

he's finally acknowledged that there is a problem, but still has no interest in fixing in. remember, he was the one that pulled the US out of the kyoto summit (or was it conference?).

There are "gross polluters" on this earth as well who weren't involved in Kyoto- i.e. China. The US produces a huge quantity of everything, a lot of which is exported. Kyoto was simply a restrictive trade law designed to hobble American production, masked as "environmentalism". As I recall, Bill "Friend of all animals" Clinton also didn't participate in that either.

Patro hits right on the nose- more often or not, the real color of green politics... is red. Environmentalism is a very effective tactic for pushing all kinds of anti-capitalist/communist mischief. :hang:

[Sandman2012]

Originally posted by Xerxes
Patro hits right on the nose- more often or not, the real color of green politics... is red. Environmentalism is a very effective tactic for pushing all kinds of anti-capitalist/communist mischief. :hang:

I agree, Xerxes. It's a shame that in modern times that so many issues are seen as being cut and dried, on one side or another. It seems if a person wants to embody a complex world-view, there is no place for him/her in our social view. I think it is possible to be a successfull capitalist as well as an environmentally concerned indiviual. Also, communism does not neccesarily imply other so-called liberal values such as environmentalism. As you pointed out, Xerxes, look at China.

If people believe in simple equations such as "conservative = capitalist = evil," or "liberal = communist = evil," then the world's problems will never be addressed in a rational manner.

[Curi0us_George]

Originally posted by ethan_h
And that ice has to come from somewhere. It's falling from the icecaps as they are being warmed, thus contributing to the volume of water in the oceans.
Ice bergs have been happenning for longer than humans have been around, and so far, the Earth has survived them. I think it will still hold up.

Originally posted by ethan_h
Slightly higher than your "few centimetres", wouldn't you think?? ;)
The last numbers I got from a professor were between 10 and 30 inches (he gave me the range that he said most of his collegues' opinions fell into). Personally, I'm inclined to believe the professor.

Originally posted by whiteflip
from what i heard alskan ice berg chuncks contain eight times more ice than normal ice. this is because it gets compacted under its own weight. what i dont understand is why this much heavy version of ice floats when it breaks off....

(maybe the icebergs are bottom heavy. heavy part on bottom light part on top.)
Alaskan ice berbs might contain 8 times as much ice as normal ice bergs, but I can promise you that they are not 8 times as dense as ice. You can't compress solids and liquids very much.