Alastair wrote:
It is fairly clear that the warming that takes us out of glacial
periods is caused by changes in the eccentricity of the Earth's orbit
which results in the planet receiving more solar isolation. But the
increase in temperature is far greater than the changes in solar
energy can explain.
Where is this claim documented? Why would it be only changes in
solar energy causing the warming? Why not a combination of climate
change factors causing the warming and the increase in CO2 concentration?
It seems that the warming is amplified by
subsequent releases of carbon dioxide from the warmer ocean. This
explains why the rise in CO2 follows the rise in temperature, and also
why the rise is so steep. The increase in temperature causes more CO2
and more CO2 causes the temperature to rise. There is a runaway
temperature rise caused by the positive feedback from the greenhouse
effect of carbon dioxide.
And yet, others claim that the amount of CO2 released from the
atmosphere is minuscule and insufficient to cause the observed
temperature increase. Who is right?
If this is a "runaway greenhouse effect," why didn't it "run away"
centuries ago when CO2 and global average surface temperatures were much
higher than now?
The melting of the Arctic sea ice is a symptom of the increase in
carbon dioxide.
Why then did Arctic sea ice diminish 1,000 years ago during the
Medieval Warming Period when there was no human industrial activity to
raise CO2 levels?
However, just as carbon dioxide is not the initial
cause of the exit from a glacial but leads to a rapid warming, so too
the melting of the sea ice is not an initial cause. However, when the
sea ice disappears there will be rapid warming as the planet tries to
adjust to the loss of albedo. It can only do that by creating more
cloud, and cloud does not seem to increase in a linear fashion with
increase in surface temperature.
The planet does not "try" to adjust to the loss of albedo. The
planet does not create clouds.
Moreover, cloud is a strong greenhouse agent. Thus after the cloud
increases to balance the radiation at the top of the atmosphere (TOA)
the temperature at the surface may be considerably than at present.
Clouds are not greenhouse gases. Water vapor is the strongest
greenhouse gas. Water vapor may or may not form clouds, depending on
atmospheric conditions. Clouds increase the albedo and reflecting energy
back to space.
There are some anomalies in Antarctica due to the ozone hole but
otherwise glaciers are melting everywhere else in the world. The
sceptics love to point out those anomalies, since it justifies their
continued use of their beloved SUV, but it is just spin.
Please don't lump me in with people driving SUVs. I am a skeptic of
anthropogenic global warming. I do not drive an SUV. In fact, I don't
drive cars at all.
Whether or not glaciers are receding (many are) or not (some are
not) has nothing to do with SUVs, runaway global warming or spin.
Glacial dynamics are as complex as climate and their actions cannot be
laid at the feet of any single factor.
The fact is that climate is spinning out of control, and there is now
no prospect that Obama can stop it, far less persuade the Chinese to
come on board :-(
Climate is not spinning out of control. There is no control,
especially not human control. Climate is changing as it has always
changed. There never has been any prospect that anyone could stop
climate change, nort even the President of the United States.
Hayduke
--
Hayduke Blogs
http://hayduke2000.blogspot.com/
--
You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change.
Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/globalchange
