Global Warming the great myth?

[Perkypete]

If man IS responsible for global warming, then what caused the global warming that ended the last ice age 10,000 years ago??
This was thousands of years before the invention of the internal combustion engine, so how do scientists explain this?
The truth is that the earth's climate is cyclical and goes through hotter & cooler periods.Trouble is that man, particularly recorded evidence, only dates back say 2,000 years at most?

[kempie]

The Earth's climate does indeed cycle through periods of warming and cooling but that does not mean we must ignore human interaction which may have played a part in 'recent' climate change.

http://en.wikipedia.org/wiki/Climate_change

Human recorded evidence may only span a few thousand years but other forms of evidence also exist...

http://en.wikipedia.org/wiki/Paleoclimatology

[shri]

I do agree that man is mainly responsible for present global warming but even the atmosphere does play a role in this context...remember the earth was predominantly by ice 10000 years ago..so the continuous process of evaporation due to sun plus the other factors such as condensation and transpiration by the plants may have resulted in the global warming....and i believe that the burns are still in our present environment even after 10000 years.....

[Loosehead]

man has control of 3% of the carbon, end of!

[mountainboo]

one volcanoe erruption probably sends more carbon dioxide etc into the atmosphere than one days worth of man made pollution. Something like that anyway

[newtron]

Loosehead, I knew you would say that. So how much of the carbon do we have to control before we can significantly affect global climate?

[Loosehead]

Krakatoa put more carbon into the atmosphere in one go than man has managed to date. That was in the 19th century, the sun dimmed for 2 years. Mankind has nothing to do with the natural cycles of the planet. It's fashionable to believe we are responsible but it's just a load of beardy weirdy clap trap. That said we can always do more to reduce polution.

[Loosehead]

Well, newtron, I suppose if we stopped cows farting we could control more but really I suppose that to affect a system you need to have significant control of the things that effect it and we haven't, I wouldn't like to put a figure on it.

[newtron]

I think that is an over simplistic view Loosehead. We have to remember that global climate is a complex system, where apparently very small changes in input conditions may have very large effects in the output.

You've heard the saying "the straw that broke the camel's back". So if we place the straw that breaks the camel's back, is it our fault?

[Loosehead]

We are a small part of the system and if it's our straw that breaks the camels back, ie induces some sort of change then that's no more significant than if for example the last straw was caused by a volcano. The Earth has existed for billions of years, reliable records go back at most 200 years, it's laughable that we can make any sort of determination on that tiny amount of data. It's like landing on the beach in Bournemouth and determining that the entire country is covered with sand!

[mountainboo]

But don't core samples taken from places like Greenland etc provide more information that go back longer than 200 years?

[mountainboo]

When is the next Ice age due?

[newtron]

"it's laughable that we can make any sort of determination on that tiny amount of data."

I agree. Yet, you come to a solid conclusion based on just one statistic.

[Loosehead]

I don't base my opinion on one statistic, I mentioned that particular statistic in this case. I have answered this question lots of times on here, do a search, I use information according to the slant of the question. I find that most eco warrior types have very little understanding of the subject and just go along with what they are told by their peers. I have done a lot of research on this subject I know a lot more than I can put out here. This is an area of great interest for me.

[mountainboo]

Loosehead, it is of great interest to me too. I have recently started studying a degree in Geosciences in an attempt to try to understand it more. I hope I have chosen the right subject as this is my main/only interest

[rojash]

"If man IS responsible for global warming, then what caused the global warming that ended the last ice age 10,000 years ago?? "

Appalling failure of logic here:
Man didn't cause this, so he can't have caused that.
This man didn't kick me last week so he can't be the man who kicked me this week.
A flat tyre didn't cause that accident, so it can't have caused this one.

[newtron]

Fair enough Loosehead. I wasn't trying to offend you. I have seen many of your answers on this subject, and youre main argument usually evolves around the 3% of the the carbon cycle that we control (I admit I have probably not seen all your answers), and I don't consider that by itself to be a good arguement. I study natural groundwater systems, and it is difficult to figure out exactly what is happening in the simplest of these systems. So I usually have problems with simple arguements to complex questions. I have no doubt that you know a great deal about the subject.

[jake-the-peg]

Lets get one thing absolutely straight - Global warming is not a myth in that the Earth IS warming

Anybody who disputes that has to explain where all the glaciers and ice shelves are going!

Next fact - Carbon dioxide and other greenhouse gasses heat up the earth they don't cool it.

Now you can argue until you're blue in the face about man's impact but the overwhelming body of scientific opinion is against you.

Even the American DOE says you're wrong

http://www.eia.doe.gov/oiaf/1605/ggccebro/chap ter1.html

This is the American government we're talking about here not Greenpeace or tree-huggers united!

There's opinion, there's denial and there's the full blown ostrich position - I think were getting towards growing feathers now on this thread

[Loosehead]

No one disputes global warming, it's the cause that is in doubt.

[Romaz]

One of the other principal causes of increased CO2 in the atmosphere is deforestation. Man is cutting down an area the size of Italy every year.

A rise of 3 degrees Celcius after the last ice age took thousands of years, in contrast, the concentration of CO2 has increased 25% since the industrial revolution, half of this rise has been in the last 30 years.

I think we need to accept a bit of the responsibilty!

[cascarelli]

Nobody's disputing that it's warming at the moment. But who's to say what the correct temperature should be at this particular point in the earth's life? Should it be as it is now, or 10 degrees higher or twenty degrees lower? What would the temperature be if man wasn't around? I'd guess that no-one knows

rojash what on earth are you on about?