Re: OT: interesting global warming quote found elsewhwere

On Aug 5, 7:53 am, James Arthur <bogusabd...@xxxxxxxxxxx> wrote:
bill.slo...@xxxxxxxx wrote:
On Aug 4, 4:18 pm, James Arthur <bogusabd...@xxxxxxxxxxx> wrote:
bill.slo...@xxxxxxxx wrote:
On Aug 1, 2:55 am, James Arthur wrote:
bill.slo...@xxxxxxxx wrote:
what is
clear is that more CO2 means a warmer climate.
That is /not/ clear.  That's supposition until verified by experiment.
There are any number of reasons that might not hold, and none have
been tested.  Nor can all such reasons be anticipated.  That's why we
do experiments.
Name a few.
Suppose clouds become denser, more reflective, or more prevalent,
fending off another 1w / m^2 ?
Then we wouldn't have had runaway global warming in the geological
past.
a) Define "runaway".

Search on "clathrate gun".

Define "runaway".

A positive feedback process where the gain is equal to or greater than
two; such process are self-accelerating. In chemistry they are the
sort of chemical explosions that lead to explosions and shock waves.

In global warming, the "clathrate gun" is the best-known example - if
the climate gets warm enough to destablise the methane hydrates in the
permafrost or on the sea-bottom along the continental shelves, the
freed methane - a potent green-house gas - gets into the atmosphere
and further warms the climate, freeing up more methane, until the
available stock of methane hydrates has all come apart.

This seems to show up in the geological record as a negative spike in
the carbon isotope ratio.

http://www.giss.nasa.gov/research/features/methane/

b) You yourself and others have pointed out this man-made CO2
    impulse has no historical precedent.  How the Earth responds,
    then, has no precedent either.

That's not what I've said. The Deccan traps and the Siberian traps seem to
have spat out comparable volumes of volcanic carbon dioxide.

There are a couple of global extinctions which seem to have been
caused by global warming

<snip>

Today's CO2 impulse is unprecedented, yet you insist the
Earth will respond according to...precedents.  That's
inherently suspect.

http://en.wikipedia.org/wiki/Deccan_Traps

http://en.wikipedia.org/wiki/Siberian_Traps

http://news.mongabay.com/2007/0426-petm.html

http://www.greendiary.com/entry/dinosaurs-got-extinct-due-to-explosions-in-india/

The last reference is the only one that even suggests the existence of
numerical estimates of the volume of greenhouse gases released by
these volcanic events - that's probably a little too technical for
English-language science reporters - but IIRR Tony Hallam's book
suggests that both the Siberian Traps and the Deccan traps would have
injected more CO2 into the atmosphere than we have done so far, so our
activities don't qualify as unprecedented, though it may take a
certain measure of mental flexibility to equate yourself to part of a
volcano

I suspect that I could have done better if I could have got into the
peer-reviewed geological literature (which is where Tony Hallam's
"Catastrophes and lesser Calamities" ISBN-10: 0198524978 ISBN-13:
978-0198524977 comes from).

--
Bill Sloman, Nijmegen
.

Relevant Pages