Re: Take a "Climate Science" Quiz

Ok, I've found your critique here. You miss several important points, which
is partly because I wrote unclearly. In other places, you try to restore
detail that is useless to the argument. You miss the part the Second Law
plays, which is your fault, not mine.

This will be hard enough to follow: I'll put my responses between lines of
dashes above and below, and delete nothing.
"Lab Rat" <robbie.buckley@xxxxxxxxxxx> wrote in message
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"Stephen Jacobs" <jacosa@xxxxxxxxxxx> wrote in message
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"Larry Gable" <larrygable@xxxxxxxx> wrote in message
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Test your knowledge of "Climate Science" with this 12-question quiz:

http://us.asiancorrespondent.com/gavin-atkins-shadowlands/climate-science-the-quiz.htm

Science content of the quiz: maybe 2%, tops.

I've been trying to reduce this one to its essentials in simple language,
without too many unfamiliar ideas.

The earth's surface layer (atmosphere, top 50 feet of water and top 4
feet of ground, roughly) is like a surge tank for heat.

The distinction between the different layers of the atmosphere is
important, too.
-------------
Why? The heat capacity of stratosphere and ionosphere is small and they
don't couple all that closely to us. They make it into the discussion
mostly because IF the properties of the stratosphere changed greatly it
might make a difference.

-----------------------

Energy is coming in from the Sun: high quality energy, effectively at a
temperature of thousands of degrees. It can, in principle, be used to do
things with little heat retained by the system, only it isn't. Most of
it hits water or ground and gets turned to heat, with an effective
temperature around 500 degrees absolute. Another fraction gets wasted
the same way in atmosphere, at a lower effective temperature.

Nitpicking perhaps, but '500 degrees' what? I assume you mean F, but
absolute implies K. Also, the nature of the incoming energy is really only
relevant to how much gets absorbed in the atmosphere.

----------------------
About 500 degrees absolute, either Fahrenheit degrees or Centigrade degrees,
that is, either Kelvin or Rankine. The point is that the incoming energy is
much 'hotter.' The relevance shows up later in the second law argument. I
don't want to let people appeal to some refrigerator, natural or
constructed, for escape.
-------------------------------


The outflow of the "surge tank" is mostly by thermal radiation.

First problem. Radiation into space is not the only method of moving heat
from ground level. Convective transfer to the upper atmosphere is
important. (In fact, it is how glass greenhouses work)

-------------------------
Huh? The heat capacity of the upper atmosphere is much smaller than that of
earth, water or dense air. Thermal coupling across the stratosphere is
lousy, too. Glass greenhouses are in decent thermal contact with a large
amount of dense air.
------------------------------

Space is a good enough vacuum, and heat conduction away from the
near-surface into deep Earth is slow enough so there isn't much else
available as a way for energy to leave. The Earth system is pretty much
a "black body" (perfect radiator) except for far-to middle infrared and
far ultraviolet to soft X-ray.

A 300K black body does not radiate at far UV to soft xray. It radiates in
the IR band, and even a cursory glance at the emission spectrum of Earth
shows large gaps compared to a black body. BECAUSE of the greenhouse
effect.
So it's pretty much a black body radiator, except where it radiates?
------------------------
Partly my fault for being a little unclear in the point I'm making. A 300K
earth absorbs a hell of a lot of sunlight in UV and soft X-ray, and it does
so by processes that don't run backwards neatly in emission. The main
reason for mentioning this is that if I only said "The Earth system is
pretty much a black body except for the far-to-middle infrared" I wouldn't
be telling the truth. Perhaps I should have said that the other band was
less relevant to the argument
-------------------------


The shorter wavelength poor-emission (and high absorption of incoming)
band is connected with the presence of any atmosphere at all that we
could use. The longer wavelength, infrared, poor-emission band is
connected with the fraction of "complicated" molecules in the atmosphere.

The second law of thermodynamics says that once energy gets into the form
of heat, there's little you can do to boost its "quality." It mostly
stays as heat.

Crap. There are many varieties of heat, some usable, some less so. The
second law simply defines how much useful work can be extracted from a
heat source. It says nothing about 'quality'.

-------------------------
What kind of lab rat are you? This is EXACTLY the point of The Second Law.
The amount of heat that comes out of a system that stores energy while the
heat moves through it is at least the amount of heat that would be released
by an ideal engine with the same input and output temperatures. I use the
term "quality" to indicate generally a reduced tendency to release waste
heat to the environment (or to be equivalent to a higher input temperature)
There are clever ways to store (hide?) energy (electrical charge, sugar,
lifting water, etc), but they can't store ALL of it. The importance of this
in the whole argument is that once the heat is in the Earth system, most of
it stays as heat.
------------------


The Planck radiation law says what wavelengths of electromagnetic
radiation a body emits for a given temperature. A body the temperature
of the Sun emits most of its radiation in the visible and UV range. A
body the temperature of the Earth emits most of its radiation in the
infrared.

But wait: that peak emission range for Earth is the wavelength range
where complex molecules in the atmosphere make Earth a less-than-perfect
radiator. In effect, they're a variable valve in the outflow of the surge
tank.

What if the valve is already fully open? Most of the wavelengths at which
CO2 absorbs are already saturated. What eventually happens to that energy?
What feedback mechanisms are there to control temperature? What part of
the spectrum of CO2 is not saturated, and what else absorbs at these
frequencies.
The latest paper I saw on the effect of CO2 levels on radiative forcing
calculated the forcing across the entire spectrum, line by line, and
concluded that the IPCC estimates are out by at least a factor of two,
without taking overlap from other absorbers into account. That translates
to a 0.2 K increase due to CO2 this century. Even the IPCC's figures don't
account for the entire rise. Given that there has been an observed
increase in temp of about 0.75 K, what is responsible for that? Fixation
on CO2 as the primary cause is simply not justified.


----------------------------
I think the rhetorical question you meant to ask was "What if the valve is
as closed as it can get?" Are you claiming that relaxation of vibrational
modes of CO2 is rate limiting here? I could easily buy that for pure
rotations, but not for vibrations. What eventually happens to the energy
absorbed by CO2 is that it's transferred to other molecules by collision.
Someone may be neglecting pressure broadening of spectral lines in some
calculations. And whose choice is it to fix on CO2? Last time I read a
serious discussion, hydrocarbons were being considered too. Basically, any
gas that isn't monatomic or diatomic figures in as an absorber, and all
gases figure in as relaxers. And human activity has effects on levels of
those complex gases.

I've said a couple times: the issue is presently at the stage where the
proper questions are along the lines "Is there a potential problem?" "How
bad could it get?" "Do we need to do something drastic?" and "If it becomes
obvious that it's getting out of hand, will drastic response be needed?"

Factors of 2 in what has happened already aren't at issue.
----------------


The levels of the "complex" gases in the atmosphere are increasing.

As they have done in the past, with no correlation to temperatures.
Historically, CO2 levels do not correlate with higher temperatures, even
at levels an order of magnitude higher than present in modern times. 95%
of the greenhouse effect on Earth is due to water vapour. If the
greenhouse effect was going to run away, it would do so every summer.

In effect, the outflow if the surge tank is getting more restricted. The
level of the surge tank (the amount of energy stored as heat in the
near-surface part of Earth) necessarily increases.

There are complexities in how things develop over time, but that's the
broad overview.

How's it read?

Like simplistic fluff. Unfortunately, sometimes complex issues require
complex explanations. Reducing global warming issues to 'CO2 absorbs heat,
so it is bad' does nothing to improve understanding of the issues.
I notice you didn't respond to my post on methane clathrates. Did you
check the cite I gave?



I didn't see anything you put up about methane clathrates. This group fills
up fast, so it may be buried too deeply. Your summary of what I said is
oversimplified in several ways. You know the line: "As simple as possible,
but no simpler." I may have missed on "As simple as possible," but when you
summarize it simpler the content is left out.


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