In today's edition of Al Gore: Liar or Idiot I offer the following to aid us in our quest to answer that question.
From (my new favorite site) Watts up with that, commenter Dr Ross Taylor brings us more from Al Gore on TeeVee:
Al Gore, on CNN yesterday, pronounced to the world that humans were responsible for the majority of CO2 in the atmosphere. Of course, no-one picked up on it. I could not believe what I was hearing:
“CHETRY: And that goes along with what David in Arizona asked you. He wants to know, please tell us what percentage of carbon dioxide is caused by human activity relative to other sources of carbon dioxide.
GORE: Well, the majority of it is caused by human activity…”
Sigh, Al, Al, Al, surely even you know that humans contribute only 3.225% of CO2, whereas 96.775% is entirely natural. Since when is 3% a majority?
Humn ... liar or idiot? I'm leaning toward "liar", but "idiot" isn't out of the running.
Now, on to the Sciencey stuff! We turn our eyes to Greenland. Which used to be GREEN, back in the days when the Vikings named it such. Before they all froze and starved after the medivial warming period (MWP) ended and we got into the little ice age. The cool think (heh) about Greenland is that we can get ice core temperature from ONE SPOT for the past 50,000 years. If you look back at the past 500 years alone, what do you see? That "hockey stick" we've grown to know so well.
But, if we look a tad further back ...
[O]ver the period of recorded history, the average temperature was about equal to the height of the MWP. Rises not only as high, but as rapid, as the current hockey stick blade have been the rule, not the exception.
In fact for the entire Holocene — the period over which, by some odd coincidence, humanity developed agriculture and civilization — the temperature has been higher than now, and the trend over the past 4000 years is a marked decline. From this perspective, it’s the LIA that was unusual, and the current warming trend simply represents a return to the mean. If it lasts.
From the perspective of the Holocene as a whole, our current hockeystick is beginning to look pretty dinky. By far the possibility I would worry about, if I were the worrying sort, would be the return to an ice age — since interglacials, over the past half million years or so, have tended to last only 10,000 years or so. And Ice ages are not conducive to agriculture.
They've got more, and cool graphs over here.
Any wonder why this, and healthcare, are both being rammed-in under the distraction of Christmas?