The data doesn't support a singular conclusion.  Historically with all the digging and the ice caps and the retro analysis of solar activity we haven't proven a long term impact of CO2 on surface temperatures.  When you look at the raw data there are sometimes literally centuries of difference between a rise in one before a rise in the other and not necessarily a causal relationship.  Fast forward to the last 150 years (a horrible sample size to determine causality for a planet over 4 billion years old) and you have an exponential growth in population and in human technological emissions and no corresponding exponential growth in the temperature curve.  

 

There's a reason that the argument shifted from Global warming to climate change to any incident of extreme weather must support our claim because nothing like that has ever happened before.  There's a reason that the argument isn't that 97% of all computer models all predicted the exact change in temperature to perfection and we talk about how out of 12000 papers 4000 expressed an opinion and an independent analysis of the abstracts of those papers and a 4 question survey support a consensus even though some authors of the 4000 papers put in the agree pile have publicly denied their believe in agcc yeh i know, not as catchy a bumper sticker as 97% of scientists agree!)  

 

1.) the data's just not there.  

 

2.) If these people were really serious then they wouldn't be wasting their time and more importantly our resources flying around on private jets and writing reports or models.  They would actually be trying to solve the "problem" by creating an alternative energy source that can get a 747 from london to New York because that's the only way that you are going to put a dent in carbon emissions.  

 

3.) Public opinion plummets when you actually tell people "well human beings represent less than 10% of carbon emissions in any given year and natural water vapor accounts for 95% of the greenhouse effect and that Co2 is still less than 1% of total atmospheric composition."  But what the hell do facts matter when you have shovel ready solutions to ensure that if you like your weather...  you can keep...  your weather!

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