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The Cycle of Global Warming 42

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CajunCenturion

Computer
Oct 24, 2003
1,571
Global Warming Dramatically Changed Ancient Forests
The findings, which appear in this week's issue of the journal Science, provide the first evidence that land plants changed drastically during a period of sudden global warming 55 million years ago, said Jonathan Bloch, a University of Florida vertebrate paleontologist and member of the research team.
(emphasis mine)
and
The warming was caused by a gigantic release of carbon dioxide into the atmosphere that was comparable to the atmospheric effects expected from human burning of fossil fuels, he said.
How much of the warming is man-made, and how much is part of the natural cycle of the earth?

Good Luck
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As a circle of light increases so does the circumference of darkness around it. - Albert Einstein
 
Jeesh...here we go again.
 
This info can be used to good advantage when filming the next catastrophe movie. The plot is:

a) everyone in China and India get an SUV and average 9 miles per gallon, first 20 minutes of movie. US cars just sit in driveway with cars runnign 24 hours a day at full idle, with drivers poking at iPods.
b)ferns start to grow to 150 ft in height, pine trees to 600 ft height, next 20 minutes
c)crocodiles morph into tyranasoaurus rexes, next 20 minutes
d) meteor hits earth and puts all of us out of business.
 
Here's the real catastrophic scenario: Alarmists convince everyone to artificially sequester CO2, which causes Earth to cool to the trend line it was on at the MWP - LIA interface gradient. In the meantime, crops fail due to increased water etc. demand. Then, billions of suddenly cold people start burning everything that will burn to stay warm - including pretty much everything Dupont has made over the last 50 years. Talk about air pollution!

Then, of course, all the hungry people start climbing over *everybody* elses back fence and breaking in to their houses...
 
back to cajun's post ...

that's the $64m (or is it $64b these days) question. politics (and money) has charged the debate so that both sides attack and counter-attack each other with near religious fervour.
 
What is the analysis from the engineering perspective? I assume the measured data we have is over too small a time aperture so can we consider the fundamentals? This is out of my field, but I am still an engineer and this could be understood from at least a likelihood analysis.

1) What is the energy falling on the area of the globe from the sun considering all wavelengths? What is the variability vs time (std. dev, pdf shape etc.)

2) What is the reflectance (or whatever the proper term is) that determines what portion of the energy makes it inside the volume of our atmosphere. Again, the variance question.

3) What is the retransmission energy, it's variance and the reflectance back again with it's variance (high frequencies turned into heat and perhaps reflected back)

4) What is the natural heat (any energy) generation, forest fires, natural gas burning, and even geothermal and again the variance stuff.

5) How does the man made energy production relate to item #1 times item #2. I am guessing it is itty-bitty and no one is arguing that point.

6) What is the man made induced variation on the internal reflectance? I think this is the key issue being considered as the only possible man made impact that could possibly impact global temperature changes. This is an awful egotistical view, but the engineering part should have a nominal estimate and a range and probability. The probability tails should be straightforward to understand. This has nothing to do with measured temp. trajectories.

7) What is the man made affect on the reflectance in #2, this could make us go cold if in the wrong direction.

8) If we start to warm up, is there a possible overcompensation mechanism that could cause us to flash over into the next ice age?

Are these the key points and does anyone have an analysis they could share o point to?
 
I'm not an expert (then again, neither is anyone else, especially the people who call themselves "experts").

But I've been into this for 10 years or so, as a hobby - starting when I was checking into hydrology throughout the 20th century.

Visigoth asks:

1) What is the energy falling on the area of the globe from the sun considering all wavelengths? What is the variability vs time (std. dev, pdf shape etc.)

The energy is pretty constant - the variable is the particle flow. Here is a basic, mostly correct, analysis:

2) What is the reflectance (or whatever the proper term is) that determines what portion of the energy makes it inside the volume of our atmosphere. Again, the variance question.

It almost all makes it inside the atmosphere. About 30% is immediately reflected back. That is the definition of albedo, which on Earth is about 0.3.


3) What is the retransmission energy, it's variance and the reflectance back again with it's variance (high frequencies turned into heat and perhaps reflected back)

The same as the incoming, except what is now being taken in by the oceans.

4) What is the natural heat (any energy) generation, forest fires, natural gas burning, and even geothermal and again the variance stuff.

It all comes, originally, from the sun.

5) How does the man made energy production relate to item #1 times item #2. I am guessing it is itty-bitty and no one is arguing that point.

Yes, man made energy (actually recovered) is extremely small - discountable.


6) What is the man made induced variation on the internal reflectance? I think this is the key issue being considered as the only possible man made impact that could possibly impact global temperature changes. This is an awful egotistical view, but the engineering part should have a nominal estimate and a range and probability. The probability tails should be straightforward to understand. This has nothing to do with measured temp. trajectories.

Right. The big flaw in the "greenhouse effect" theory is that the great majority of energy transporting back up through the troposphere is via convection - air masses moving up and down. The "greenhouse effect" has no effect on convection.


7) What is the man made affect on the reflectance in #2, this could make us go cold if in the wrong direction.

True, but the primary anthropogenic effect now is stripping of vegetation through overuse, which decreases the heat turned to flora and increases the sensible heat.

8) If we start to warm up, is there a possible overcompensation mechanism that could cause us to flash over into the next ice age?

It could, but there are many short term (geologically) negative feedbacks keeping us in this climatic regime - not the least of which is floral response to increased temperature, which increases CO2 by way of the warm coke effect out of the oceans, but also arctic sea ice which regulates the sink of CO2 into the ocean - and that increasing temperature increases evaporation, and what goes up must come down, so precipitation increases.

Are these the key points and does anyone have an analysis they could share o point to?

Here are some links:
 
LCruiser
Very good info...
A star from me


Regards

pennpoint
 
rb1957

"attack each other with near religious fervour."

Now you've done it, brought religion into the discussion. Won't be long now before Nazi's are called out.[thumbsdown]

Life is what happens while we're making other plans.

Wally
 
LCruiser, thanks for taking the time to concisely respond and open my eyes to new issues. You have the ability to explain key points with few words, that it a good trait. I appreciate it.
 
Thanks VisiGoth. You can see, if you look closely at them, that the CO2 variation follows the temperature variation, so it's kind of doubtful that CO2 caused the temperature change (cause seldom trails effect...).

Also, lots of chatter going on now about Urban vs. Rural temp trends - Here's a graph of that from California:
 
The article is right in suggesting that consensus science is not science. Peer-reviewed, published papers are. Einstein went out on a limb and publihsed, but it took years to vindicate him. How many published, per-reviewwed papers, are there that rubbish global warming?
The links below show that on the contrary, the US government is trying to get the head climatologist in NASA to shut up, as he tries to speak about the issue.
maybe the Bush administration is busy buying up property on the southern Georgia border with Florida, so that when the sea levels come up and flood Florida, they can sell it as prime beachfront property
 
"Jeesh here we go again"

A pretty relevant comment.

I suspect that many important issues get talked out early on i.e exhaust peoples tolerance for the discussion before the discussion is actually resolved.
In other words, after a while all they do is note the headlines because they are pretty zoned out by all the chatter they don't understand.
Grabbing a sound bite last week it seems further debate is futile as the media report we have gone beyond the point of no retunr i.e. the point at which we can do anything about it.

Great, I'll go buy that SUV after all.

By the time the debate centres on hard and fast facts ... which of course we don't have yet, mosyt people have already stopped listening.

That's probably why we still have a flat earth society.

The Global Warming issue also gives the lie to all those disaster movies and films like Jaws where the hapless Mayor is too frightened of the effect on toruism etc to raise the alarm unless he sees the damn shark eat someone with his own eyes i.e. until it is too late...

In real life, it seems, we have the opposite with every man and his dog only too happy to swallow the whole speculation hook line and sinker and accept it blindly as fact.

Thus, in all probability, the Mayor in Jaws should have taken out an ad claiming a whole shoal/pack whatever of maneating sharks were eating tourists as fast as they could and it would have probably doubled tourism....



JMW
 
davefitz said:
a) everyone in China and India get an SUV and average 9 miles per gallon, first 20 minutes of movie. US cars just sit in driveway with cars runnign 24 hours a day at full idle, with drivers poking at iPods.

I am too dull to get the catastrophe here. Is the development outside the developed nations a catastrophe or the already existing SUVs (which average 9mpl)?

In later case, I would save 20 minutes of film cost if I were directing it.

In any case, it is not a good idea. Warming must have been a global contribution.

 
For a good yarn that's also a well-documented commentary on the "global-warming industry," read Michael Crichton's State of Fear

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How much do YOU owe?
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One can argue both sides of this issue till we're all in the ground- the main point to be made is that as engineers, we are supposed to be designing things and systems to be more efficient - using resources more efficiently, conserving fossil fuels, and minimizing our footprints on the planet, regardless. Global warming may be a natural cyle that we humans, living only a short time, and having accurate records only going back a micro-second in geological time, don't really have a grasp on. Let's just practice smart engineering, making things more efficient, using less energy and less resources, to accomplish our means to our ends.
 
Which would be fine if fuel efficiency was a zero cost option. It isn't.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
 
for my money, I say we quit spending on the environment and build a liferaft off of this planet!

Wes C.
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When they broke open molecules, they found they were only stuffed with atoms. But when they broke open atoms, they found them stuffed with explosions...
 
There are many more cost effective options than reducing CO2 - which hasn't even been conclusively proven to be a problem. Land use changes, albedo from e.g. Chinese power plants, etc. also play a part.
 
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