Hi David,

--- In energyresources@yahoogroups.com, "dmathew1" <dmathew1@...> wrote:
>
> Hello Everyone,

> A casual reading the material is sufficient to conclude that
> humankind has pushed the atmosphere into uncharted territory with
> the pollution generated by fossil fuels. While we may not know
> with absolute certainty the consequences of these changes, I think
> it safe to conclude that they are extremely dangerous and pose an
> existential threat to civilization.
>

A more detailed reading shows some interesting things. For example even
though greenhouse gasses are at their highest level in 800,000 years,
the paper 'Eight glacial cycles from an Antarctic ice core' figure 5
shows that our Holocene interglacial is still not as warm as the MIS 11
interglacial of 400,000 years ago. That figure shows that while
greenhouse gasses were lower temperature rose for thousands of years to
a level warmer than today.... without an SUV in sight.

We are constantly told that climate change needs to be explained by
something if it is not caused by mankind.... but as we see from the ice
core data during MIS 11 there was long term global warming without
mankind to blame.

And why do so many of these EPICA papers focus on the MIS 11
interglacial? Because orbital conditions today are very similar to
orbital conditions during the long MIS 11 interglacial with very low
eccentricity. Just imagine a period with similar orbital conditions to
our current Holocene interglacial where temperature was not steady but
actually rose for thousands of years to a much warmer level that today
even though we have much higher greenhouse gas levels.

Another interesting graphic from that paper is figure 2, panel b. This
is the EPICA temperature proxy which shows that most previous
interglacials were warmer than our Holocene.... again warmer naturally.

Cheers

Jim