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Vinnyb:
Probably talking about the 'Hockey Stick' curve produced by Mann et al? see attached. I haven't seen all of Inconvenient yet, so not sure if thats what you meant.
the jist is that it over the last 2000 years or so, the rate and amount of warming is the highest it has been. Conceivably thats human impacts. Another guy (Ruddiman believes you can see human impact back 1000's of years due to changes in forest patters via farming. I'm less than sold on this, but he is a big name in climatology)
Boss-man..
We do sediment cores, not ice-cores. But Alley et al (the ice core guys from Greenland and Antarctica) have data that extend back ~800,000 years that show a warming trend as well.
the Biggest problem with this is that any change over the measured time is less than the annual/decadal/multidecadal noise in the signal. Does that mean I think it isnt happening, no I believe it is reality, but as RRockcrawler pointed out, how much is human and how much is natural... probably the most compelling points is the 'Keeling curve" measured at Mona Loa. Shows a marked increase in CO2 since 1958. If you see there is an annual signal, but the overall trend here is much greater than that noise.
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