[cogitator]

Except that, in the past, the temps were 4-6 degrees higher with an ice core reading for CO2 of 280ppm; why is that?

We need the higher resolution graph:

Peak temperatures of each interglacial do briefly exceed the fairly stable temperature of this interglacial. Note the time-scale. It takes a long time for the global temperature to fully equilibrate with the increase in atmospheric CO2. Over scales of several thousand years, the full response of the system can be perceived. At this point I speculate that at a certain global temperature, some negative feedbacks kick in to start moderating the temperature.

Not much comfort for the current trends there.

[Senator_Blutarski]

A few observations regarding the chart you posted:
(1) The rise in CO2 levels seems to lag behind the rise in temperatures. I find that puzzling.
(2) The current rise in temperatures began about 17,000 years ago, long before human development altered the CO2 levels on earth.
(3) If the temperature has "stalled" at a high level, it appeared to do so before the CO2 levels rose.

I'm struggling to understand the basis for the conclusions regarding man's involvement in the current global warming.

[ChessExpert]

Nice graph. How do we temperature variation from ice core samples? (I hope it's not inferred from CO2 concentration).

[Chaguito]

I'm not a climate scientist, but I can't help seeing in the structure of the ice core graph the tendency for minima in temperature to occur before minima in CO₂, that is, a new temperature rise begins before CO₂ levels begin to rise. I recognize that the data may not be precise, but there is a lot of it.

I haven't refreshed for a while, so you may have already responded, but I'll ask again, is it shown unequivocally that the correlation implicates carbon dioxide as a cause of temperature rise? or vice versa?