Billy wrote:
Doug Freyburger wrote:

The Sahara used to be grassland, as was most of central Asia. How much
was human grazing and farming and how much was natural climate change?
Very hard to tell after the fact.

What is "natural climate change"?

Change that is not caused by humans. There's been a lot of it in
geological time. Enough to ask if the human contribution in the current
trend is large or small. And that's independent of the real issue that
you point out in the graph - If global warming isn't really a good
thing.

The graph on
http://en.wikipedia.org/wiki/Geologic_temperature_record#Recent_past
indicates that the planet was "naturally" getting cooler.

The graph also shows that life in general has done very well during the
warmer geological periods. We're all doomed - The history of life
thriving during warm periods proves it! We're all doomed - Humanity
evolved during the recent swings and highs. Our prehistoric ancestors
have already been through several ice ages and warming periods. The
"we" part is specific parts of human culture not humanity in general
and not life in general.

Independent of the size of human contribution to global warming that's
the interesting point - Earth's life thrived under warming conditions.
Ancient humanity thrived under warming conditions. Therefore global
warming *must* be *entirely* human caused and we're all going to die
as a result of it! It's political BS at its finest. It ignores what has
actually happened during prior warm eras.

Even glancing at the graphs tells a different story. Life and humanity
have thrived under warmer conditions across geological time. Except for
folks living in Florida which will eventually be innundated, exactly how
again is life and humanity thriving a disaster? Last time I checked
there are planes, trains and automolbiles capable of evacuating Florida
in a lot less than the several centuries it will take for it to flood.
We'll need to replant the citrus groves elsewhere, completely
disasterous.

The degree of human contribution just doesn't matter in real terms -
Life in general and humanity in specific has thrived on Earth during
eras of warmer climate.

Is it bad just because it's different? Really? I look at those graphs
and I don't buy it. I look at those graphs and I wonder why I support
green energy sources like wind, solar and nuclear. Because fossil fuels
are limited resources, that's why.