For the skeptics: suppose that humans would emit 6,000 billion tons of CO2 in the next 100 years (that's about 2,000 billion tons of carbon).

What will happen ?

You can believe what you desire. it is not my job to change that, I have better things to do. I am not a scientist, but I can understand GREENHOUSE gases have greenhouse effect (they are called GH gases for a reason), even at global scale. It is not my problem if you don't believe this.

QFT

again QFT

I am more likely to believe scientist on this field (and their consensus) instead of sceptics, and as I have already expressed several times, I hate conspiracy theories, and this anti AGW thing is one of them. Why do so many people want to believe CO2 has no effect? Supporting big oil companies and this fossil fuel consuming global economy.

No, it's a misunderstanding that people have a right to believe something different than what you believe in.

You are continuing to beat a dead horse with this.

If I was into emoticons, I'd use the head-banging-on-the-wall one here.

Just saying.

What did the wall ever do to you to make you so hostile towards it?  Are you wall-ist or something? 

Sigh.  Just because something is a green house gas doesn't mean it is a significant driver of temperature.

When you jump up and down, you are, by definition, affecting the earth through the transfer of your kinetic energy.  However, that doesn't mean that it's measurable.

Saying that CO2 is a greenhouse gas and therefore if it goes up it is going to cause a measurable rise in temperature.

As a reminder, this graph, which comes from NOAA.gov makes it patently obvious that CO2 isn't a driver:

Take a look at how temperatures go back down BEFORE CO2 levels go down.  I don't know if the issue here is whether I'm dealing with people who have cognitive dissonance or simply are just not familiar with reading graphs.  I mean that with no disrespect intended. Lots of people just have a hard time grasping the tools of statistical analysis.

Geo asked what it would take to "prove" global warming.  That's a nonsensical question.  The question isn't whether we believe in climate change. The question is whether we believe man-made CO2 production is having a significant effect on global temperatures.

When discussing these issues, having done so over many years, I routinely get the impression that AGW advocates don't really understand the links or the IPCC report.  

One can believe in climate change without believing that humans are the cause.  One can believe that humans are the cause without believing that CO2 is having a measurable affect. Unfortunately, too many leftists, like in so many other fields of study, don't seem to be able to make these distinctions.  So I will say it again: There is zero evidence that CO2 levels have been a primary driver of worldwide temperature increases.  That does not mean that CO2 isn't a greenhouse gas.  

Carbon Tetrachloride is also a greenhouse gas too. That doesn't mean it is having a measurable effect on temperatures. Chlorodifluoromethane is also a greenhouse gas and levels of that have gone up a LOT more (like 3X more) than CO2.  

The problem, IMO, is that leftists tend to be intellectually sympathetic to any hypothesis that ultimately can be blamed on wealth (and let's face it, CO2 production is the result of our increasing global standard of living).  So they don't really investigate beyond that hypothesis (even though, btw, the IPCC does talk about Carbon Tetrachloride and Chlorodifluoromethane and their increases but the typical AGW advocate hasn't actually bothered to read it.

What galls me are these lay people who have never bothered to do any of their own research into the matter (and I don't mean climatology I am simply talking about reading their reports before they've been politicized by non-scientists). Instead, they get their info from politically motivated websites and just regurgitate it smugly with nonsense like "Oh, you don't believe the scientists".  

In fact, I do believe the scientists. I just wish more people would read and understand what they say instead of reading papers written by those with a political agenda.

You want me to buy into AGW? Ok, explain how historical temperatures (including ones in the 20th century) can significantly drop while CO2 levels are either still high or actually climbing.

You'll be back. It's like a bad wreck on the freeway - can't 'not look'.

It is irrelevant here, as we want to find out what causes temp to go up (or CO2 to go up).

BTW this graph does not prove that CO2 is following the rise of temperature, just check the first major event, there the red line starts increasing first.. And the others are simultaneous, maybe the blue is sometimes earlier, other times not.

I wanted to comment on that graph before but somehow I forgot.

Blue line affects the red line, or the opposite.. Only the correlation is sure.

hm you were right

It is so bad I have no time to fully comment on Frogboy's post, and I even messed up the letter types, it is not supposed to be bold. Maybe some hours later.

New definition of black hole.

I already attempted to explain why pre-historical era CO2 levels and temperatures (the majority of the graph) and current human driven CO2 levels and temperatures are not very comparable for a number of reasons. There are many factors as to why CO2 was not a primary driver of temperature increases back then. Factors that raise temperature and factors that decrease CO2 levels are different in these different eras. Read about the carbon cycle and the number of ways in which we've disrupted it and it makes more sense. It's also a process of elimination - there is no other plausible factor to explain the increases in temperature - both surface and ocean, melting ice, etc. etc. I think there are a number of genuine areas of contention - amongst scientists as well - on the topic of AGW - but that we are responsible through disruption of the carbon cycle is not one of them.

This is like talking to the guards in Monty Python.

It's very simple: IF CO2 has a significant effect on global temperatures THEN temperatures shouldn't repeatedly drop BEFORE CO2 levels drop.  The fact that this happens over and over (and that temperatures go up before CO2) indicates that temperature is not measurably affected by CO2.  It does imply that temperature affects CO2 but if that's the case, then we need to quit sweating about man's impact on CO2 levels for temperature reasons.

Hm, now I am starting to have questions about this.. But still in unnatural circumstances it may behave differently, unnatural amount of CO2 and unnatural amount of disturbing forces (what mankind is doing). And the increase of global temperature and the increase of CO2 in the past 200 years.. It would be really strange if there was absolutely no connection, as we know much of that CO2 comes from burning fossil stuff.

But no matter what's the truth, we should reduce the CO2 emission as much as we can, that's why I find this debate a bit.. strange, like you want to legitimate the emission of this much CO2 without knowing the possible effect for sure.

Oh, and there is a misunderstanding somewhere, I never stated that I think CO2 is the major cause of global warming, I think it has a role in it, with many other factors. And there are stronger greenhouse gases as well..