Gases diffuse so that the concentration of any one gas is essentially the same at all altititudes. At least they don't exist in layers according to molecular weight.
TomT

Bush? HaHaHaHaHa! (I realize you're joking, but its disturbing to think that there are some who would read that suggestion with a straight face.) Bush doesn't have the education let alone the concern for fellow human beings.

__________________
"Insignificant molehill sometimes more important than conspicuous mountain." - Charlie Chan

But now you are talking about 400 to 600 million years ago. Pangaea wasn't even around back then. Conditions were completely different, as were the lifeforms. We don't know what caused the rise and fall of the CO2 levels then, because we have simply not enough information, but I don't see how it has any significance to our current situation. We do know what causes the rise now, and we do know that the current rise has taken us to a level that is clearly higher than anything in the past 500,000 years.
In what way are these measurements more accurate than the ones you rejected at first because of the margin of error? Double standard?
They don't meaasure the same thing, by the way, so a difference in them does not indicate an "error" in either of them. Satellite and ballon measurements measure the troposphere temperature, not the surface temperature. Of course, it is the surface temperature that has the most immediate impact on us.
As for the 15% loss in 18 months: I don't know your source, so I can hardly comment on it. But for a rise of 0.6° (+- 0.2°) in a century, this means that your anecdotical last year and a half is 0.09 (+- 0.03°) cooler. And this is evidence of what? That the satellite and balloon thermometers are extremely accurate? That the temperature does not lineary or exponentially rise year after year? Something else?
No idea what you try to show with this, but it has no significance. 5 year trends are a minimum, and 10 year trends are better to discuss the climate. Yearly (or 18 months) figures to disprove GW are not more interesting or convincing than the use of one hurricane to prove GW.
I'll ignore the strawman, and just point out the paradox in your statement. You have actually just confirmed that CO2 levels have risen 35% "in the blink of an eye". The only serious reason known for this is that it is (mainly) caused by humans. Please give your competent other explanations, if any.
Um, yes, we are going to a period of warming, that's what is called GW. I'm gald you agree there. The discussion focuses more on the two A's of AAGW (Apocalyptic Anthropogenic Global Warming): is the warming this time caused by humans, and will it have catastrophical results? My take on it is that yes, it is (mainly, not completely) caused by humans, but no, it will not be apocalyptic, but it will have serious implications, and the negative ones will outweigh the positive ones. I have good reasons to believe that it is human caused, I have mostly gut feelings about the effects (apart from some basic things).
We weren't around when the levels were higher, so your "and we are all still here" is irrelevant. There weren't mammals around back then, let alone humans.
I have stated before that the Earth doesn't care about the current warming, and probably life will go on just as well (except when a Venus scenario would occur, which seems highly unlikely). I'm more concerned about us, humans, and on the kind of life we have now, and the impact on many other vertebrates as well.

__________________
Knowledge is a curse, but ignorance is worse

Why do you just repeat your previous argument? I had heard it the first time, and it is still as unconvincing.
Just a figure from Wikipedia:
And another one from the same page:Which means that the increase we measure now over a hundred years (no matter what the cause), is as big as the increase between an ice age and a warmer period, and that,as has been said, the current (and increasing) level is by far the highest of the last 650,000 years (and probably much longer, but the records are not so good and so continuous earlier).
So it looks like we can make and have made a serious impact, and that our contribution, or the effect it has, is much bigger than the effect of volcanic emissions, simply because it is much more sudden, more intense.
__________________

__________________
Knowledge is a curse, but ignorance is worse

Why not? Twenty years ago Al Gore positions on a variety of topics was much different than they are now (Pro-Life and Pro Gun). Senator Robert Byrd used to be in the KKK and he's changed. Plenty of people in politics change thier views and not just to get more votes, so why not Bush? My own views on the environment now are much different than they were twenty-five years ago.

What the Global Warming folks need to do is get rid of people like Al Gore or George Clooney as their spokesmen and find somebody on the right, like McCain to support the cause.


BTW, Did you know that George Bush has more education than Al Gore? Also his undergraduate grades were better than both Gore or Kerry.

Alright, we have this no politics rule. Sometimes it is really clear that someone started the ball rolling and we'll issue a warning. In other cases, we start with a politically charged topic, like this, and it slowly gets out of hand.

I've closed this thread. No one is warned, but everyone is asked to please be more careful about this sort of thing in the future.

__________________
Forming opinions as we speak