Actually, the role of CO2 in the greenhouse effect has been understood for over a century. Arrhenius calculated in 1896 that a doubling the amount of CO2 (then) in the atmosphere would lead to a 5-6C increase in the average temperature...
...Theoretically, this sensitivity is explained by CO2's strong greenhouse effect (10-20% of GH warming is due to CO2, compared with 30% for H20) combined with its large atmospheric longevity.
this was the most useful post in this entire thread, i think. thank you very much for actually posting some serious argument, rather than simply attacking the
character of those who have offered counter argument.
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i've posted previously regarding the use of the term "denier" in the GW/AGW context. i thought that perhaps my point had, hopefully, been understood by others, but it appears not.
the term "denier" is condescending. using such a term will only encourage emotional based discourse. if you have no interest in good argument, then please, continue referring to others as "deniers", because it will only make the readers resent you, and stack the deck against anyone changing their mind. it's much more difficult for one to accept that one has been incorrect if the opposing argument comes from a dick, so if you care at all about GW/AGW, stop being dicks.
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i've posted previously regarding the personal attacks of those who offer counter argument-- such as junkscience.com-- and suggested that the very specific arguments made by junkscience be challenged instead.
under the assumption that junkscience.com is run by hitler, it is still much less productive to attack hitler than it is to attack hitler's arguments. despite the fact that hitler may have personal or financial bias to make any array of claims, and despite the fact that hitler is, well, hitler, he could still be right, at least, some of the times.
those who offer opposing argument seem to be consistantly dismissed as shills. as i spend a great deal of time arguing with the 911 truther folk, i can't help but notice that the same tactics are used by 911 truthers.
the fact is, the specific arguments made by those with opposing argument are easily accessable for debunking, so there's no excuse to simply dismiss the arguments. while you may not like it, those that are doubting GW/AGW are likely going to interpret the constant dismissal of oppositional argument as an inherent weakness of those arguing for GW/AGW.
in example, pointing out stupid mathematical errors previously made by those arguing against the hockey stick graph, rather than addressing the oppositional arguments, is both unproductive and inefficient.
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i'm also annoyed at the continual bickering regarding scientific consenses. from what i can gather, it seems to me that we all (mostly)-- even many of the evil "deniers"-- agree that:
1. the earth currently seems to be warming.
2. CO2 in the atmosphere causes heating.
3. humans are contributing to the CO2 in the atmosphere.
so, at least to some extent, we all agree that humans are, at least, partially responsible for the earth's current warming trend.
it seems like to me that there is good room for debate regarding how significantly humans are impacting the climate. while i've attempted to study this issue for quite awhie now, i still think i'm far too ignorant to hold any sort of conclusions that i can put any stock into. i'm also not any closer to understanding exactly what the scientific consensus is regarding the extent to which humans are contributing to the climate. the sense i gather from major media-- i don't tend to find the major media very reliable--, for example, leads me to believe that the scientific consensus is that humans are the main factor in the recent, observed warming, but when talking with relatives and others who are actual scientists-- anecdotal, i know-- i am lead to believe that the consensus is much less certain. the question i am faced with, then, is what evidence is less reliable: that which is presented by the major media, or that which is anecdotal?
i honestly don't understand how so many of you, on either side, can be so certain in your conclusions. before that gets me labeled as a "denier", let me make it abundantly clear that i certainly agree that the earth is warming, and that humans certainly play a role. i'd like to believe that the role is insignificant, but in the past months i've seen evidence enough that i've changed my mind, and i think that there certainly is a significant A in the GW-- i'm just not so sure that i'm right.