here's those cranks at NASA - what are they like? 
http://climate.nasa.gov/evidence/
time to put this debate to bed (plus i need another 16 posts)
Nasa's figures are not their own, they come from the UN IPCC.
"Average global temperatures in the Early Carboniferous Period were hot- approximately 20° C (68° F). However, cooling during the Middle Carboniferous reduced average global temperatures to about 12° C (54° F).
Similarly, atmospheric concentrations of carbon dioxide (CO2) in the Early Carboniferous Period were approximately 1500 ppm (parts per million), but by the Middle Carboniferous had declined to about 350 ppm -- comparable to average CO2 concentrations today!
Earth's atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former geologic times, our present atmosphere, like the Late Carboniferous atmosphere, is CO2- impoverished! In the last 600 million years of Earth's history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm.
Global Temperature and Atmospheric CO2 over Geologic Time
Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).
There has historically been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period (200 mya), average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm -- about 18 times higher than today.
The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today-- 4400 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.
Temperature after C.R. Scotese http://www.scotese.com/climate.htm
CO2 after R.A. Berner, 2001 (GEOCARB III)
http://www.geocraft.com/WVFossils/Carboniferous_climate.html
Debate over? No, Bannjaax, it's only just beginning.
and the IPCC collate their report from gathering data across a wide spectrum of respected scientific studies, but no, a few cranks shouting about how theres no problem has about as much weight 
your argument about differences in temperature, the differences you're quoting took millions of years to adjust, what we've done in the last 100 years is comparable - you've made my point for me - cheers Nick 
Maybe it's me, but I haven't a clue what the highlighted text means. :-?
maybe referencing levels of CO2 millions of years ago helps you sleep, the planet at that time was undergoing huge changes in the atmosphere a very volatile period and yet in our short industrialised time, we've had a much greater impact
i'm not sure what point you're making myself, other than the atmosphere was different millions of years ago? we should be looking at whats happening now and ways to slow it down. now this is where we agree Nickbat - one more time - we cannot do anything to stop what we're doing to the environment, nor should we spend billions on fruitless measures that don't go far enough - whilst i totally agree theres some terrible, alarmist articles on climate change - (i agree with you and zulu on that) just because a few cranks go to far, doesn't dismiss the overwhelming body of evidence that points to industrialisation being a significant factor in recent climate change.
i smoke. i know it's bad for me. all medical evidence would appear to suggest that smoking can cause a number of fatal diseases and yet, within a few minutes i could cut and paste reams of websites stating that smoking is harmless - doesn't mean i dismiss all the medical science - and it still doesn't mean i've given up smoking
my point (i'm getting to one!) is that i know without doubt we're affecting our own atmosphere and i know we should be doing something, but i also know i don't worry about it significantly enough to actually do anything

it's like me trying to prove to you that God doesn't exist - all evidence and science is behind me and yet if you believe in God no reason will suffice - you'll simply choose to believe what you like - and thats fine by me 8-)