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Happy Earth Day

Old 05-01-2009, 08:50 AM
  #31  
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Default Re: Happy Earth Day

Originally Posted by jungle View Post
So, what is the correct temperature for Earth?
They've brought the heart attack patient in and they're getting ready to crack his chest open for the bypass and you're standing there saying:

"Why the surgery? I happen to know that a diet low in fat, salt and cholesterol together with a regimen of moderate exercise is what's necessary for a healthy heart."
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Old 05-01-2009, 08:57 AM
  #32  
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Originally Posted by N2264J View Post
They've brought the heart attack patient in and they're getting ready to crack his chest open for the bypass and you're standing there saying:

"Why the surgery? I happen to know that a diet low in fat, salt and cholesterol together with a regimen of moderate exercise is what's necessary for a healthy heart."

You are trying to convince us an emergency exists when in fact there is none. The patient has arrived in a healthy state and you have started up a chainsaw.
We can get back to a climate discussion whenever you are ready.

Again, what is the correct temperature for Earth?
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Old 05-01-2009, 09:19 AM
  #33  
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Default Impact of Global Warming

Unnecessary comment removed for reasons of civility. Self-policing in action.

Last edited by 11Fan; 05-01-2009 at 09:35 AM.
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Old 05-01-2009, 11:09 AM
  #34  
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Originally Posted by 11Fan View Post
Unnecessary comment removed for reasons of civility. Self-policing in action.
Admirable self restraint. I tip my hat you 11Fan.

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Old 05-01-2009, 11:35 AM
  #35  
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Here is a target, anyone care to try shooting a few holes in it? Just for sport you understand.






In a paper that will appear in the Journal of Geophysical Research - Space Physics, Dr. John Emmert and his colleagues, Drs. Michael Picone, Judith Lean, and Stephen Knowles, report that the average density of the thermosphere has decreased by about 10% during the past 35 years. The thermosphere is the highest layer in the atmosphere, and begins at an altitude of about 90 km (56 mi).
The study utilized orbital tracking data on 27 space objects that have been aloft for over 30 years and whose closest approach to the Earth ranges from 200-800 km (124-497 mi). The Space Shuttle typically orbits at 300-450 km (186-279 mi), and the International Space Station is at an altitude of about 400 km (248 mi). Although the atmosphere is extremely thin in this region (the air at the Earth's surface is a trillion times thicker), it is enough to exert a drag force on satellites, causing their orbits to decay slowly and ultimately resulting in a fiery disintegration at lower altitudes. By analyzing changes in the orbits of the selected objects, the scientists derived the yearly average density encountered by each object. After adjusting for other factors, the data from every object indicated a long-term decline in the density of the thermosphere.These new results verify and significantly expand a limited earlier investigation, by scientists at The George Washington University, which also used orbital data to derive a long-term decrease in thermospheric density. The new NRL study utilizes more orbital data over a longer period of time and employs more precise analysis methods. By carefully examining all potential sources of error, the NRL team has provided solid evidence that the trend is neither artificial nor the result of physical processes other than internal atmospheric cooling.
Based on the NRL analysis and projections of carbon dioxide levels in the atmosphere, the density at thermospheric heights could be cut in half by the year 2100. This change may present mixed blessings: while operational satellites will be able to stay aloft longer, using less fuel, so will damaging spacecraft debris, potentially increasing the frequency of collisions.
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Old 05-01-2009, 11:42 AM
  #36  
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Originally Posted by N2264J View Post
When dealing with systems as huge as the global climate, you're working primarily with probabilities. You can't duplicate this stuff in a wind tunnel.

Look, we've been through all of this before. In the 50s, peer reviewed science started to link cigarette smoking with lung cancer. The tobacco industry hired medical doctors, celebraties and quack scientists to publically characterize those papers and studies as "junk science."

That worked for a while but today you'd be hard pressed to find someone who doesn't think cigarette smoking causes lung cancer.

We have to get this right because the consequences are global, not just some individual smokers dying of cancer.
You'll be amazed to discover that you've happened on a subject upon which we agree--we do have to get this right.

You are right on target when you say you can't duplicate this stuff in a wind tunnel. Solar weather, ocean temperatures, atmospheric convection, tropopause height, vulcanism, cloud coverage, precipitation patterns, terrestrial vegetation, and thousands of other factors--many of which I'm sure we haven't thought of yet. And yes, atmospheric carbon dioxide (all .0387% of it) counts too.

We can't build an adequate climate model so some scientists have gone with computer modeling. These models describe exactly what has already happened. They were pretty good at predicting the near future as long as the temperature was going up. As far as I know, not one computer model called the global temperature decline that began in 2003. I would not call this settled science.

So, we do have to get this right. And it is about probabilities: draconian environmental legislation will certainly curtail individual liberty and reduce general prosperity; the same legislation might have a little effect on the massive, incompletely understood, dynamic system that is our climate. Seems like a bad bet to me.

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Old 05-01-2009, 01:29 PM
  #37  
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Default Re: Happy Earth Day

Originally Posted by jungle View Post
Here is a target, anyone care to try shooting a few holes in it? Just for sport you understand.

It looks like you left a couple paragraphs out of the middle of this American Geophysical Union/Naval Research Lab joint release.

...After adjusting for other factors, the data from every object indicated a long-term decline in the density of the thermosphere.

This decrease in density had been predicted by theoretical simulations of the upper atmosphere's response to increasing carbon dioxide and other greenhouse gases. In the troposphere (the lowest layer of the atmosphere) greenhouse gases trap infrared radiation, causing the well-known "global warming" effect. Higher in the atmosphere, above about 12 kilometers [seven miles], however, these gases actually enhance the ability of the atmosphere to radiate heat out to space, thereby causing a cooling effect. As the amount of carbon dioxide increases, the upper atmosphere becomes cooler and contracts, bringing lower-density gas to lower heights. Consequently, at a given height, the average density will decrease. Because each layer of the atmosphere rests on the layers below it, small changes at lower altitudes become amplified at higher altitudes. The NRL study found that the observed decrease in density depends on height in the same way as predicted by the theoretical simulations, indicating that greenhouse gases are a likely source of the change.

An extreme example of the greenhouse gas effect can be found on Venus, whose atmosphere is 96 percent carbon dioxide (compared to trace amounts in the Earth's atmosphere), resulting in a very hot lower atmosphere 400 degrees Celsius [800 degrees Fahrenheit] and a very cold and compact upper atmosphere.

These new results verify and significantly expand a limited earlier investigation, by scientists at The George Washington University, which also used orbital data to derive a long-term decrease in thermospheric density...
Increasing greenhouse gases lead to dramatic thinning of the upper atmosphere

Last edited by N2264J; 05-01-2009 at 01:46 PM.
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Old 05-01-2009, 02:11 PM
  #38  
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So where does this leave us?

"Higher in the atmosphere, above about 12 kilometers [seven miles], however, these gases actually enhance the ability of the atmosphere to radiate heat out to space, thereby causing a cooling effect. As the amount of carbon dioxide increases, the upper atmosphere becomes cooler and contracts, bringing lower-density gas to lower heights."

One might also conclude that raising CO2 levels in the upper atmosphere cools the Earth. In any event, it does not explain fully why we have a recent cooling trend.
I can understand your eagerness to show that CO2 is a cause, the question remains though, is it the only cause, what does it cause and can we control climate solely by adding or subtracting sufficient quantities of CO2?
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Old 05-01-2009, 02:16 PM
  #39  
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Originally Posted by N2264J View Post
When dealing with systems as huge as the global climate, you're working primarily with probabilities. You can't duplicate this stuff in a wind tunnel.

Look, we've been through all of this before. In the 50s, peer reviewed science started to link cigarette smoking with lung cancer. The tobacco industry hired medical doctors, celebraties and quack scientists to publically characterize those papers and studies as "junk science."

That worked for a while but today you'd be hard pressed to find someone who doesn't think cigarette smoking causes lung cancer.

We have to get this right because the consequences are global, not just some individual smokers dying of cancer.
Actually you can't PROVE that smoking cigarettes CAUSES cancer, you can only say it will increase your RISK of cancer, because otherwise there would be a direct correlation from smoking to lung cancer... (I know, yell at me all you want, but try to argue with the late 90's person who has smoked and eaten red meat all their life, and don't have cancer yet... And then you can tell it to the people who have never smoked a day in their life, and get diagnosed with lung cancer...)

As to that 2nd example, that plays into the fact that "science" has to be able to be proven correct as well as proven incorrect. You cannot PROVE that not smoking cigarettes will prevent you from getting lung cancer...

That's essentially the point the people who don't believe in global warming (myself included) are trying to make... You can trot all the celebrities out who believe it, but that doesn't PROVE anything, it just scares the uninformed...

Last edited by whatthe6789; 05-01-2009 at 02:20 PM. Reason: Added the 2nd paragraph...
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Old 05-01-2009, 02:30 PM
  #40  
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Default Re: Happy Earth Day

Originally Posted by jungle View Post
One might also conclude that raising CO2 levels in the upper atmosphere cools the Earth.
If that's what you got out of this, it just amplifies why interpreting scientific
data should be left to the scientists familiar with it.

That's not what it's saying. They're talking about cooling in the upper atmosphere (above 7 miles).

In the troposphere (the lowest layer of the atmosphere) greenhouse gases trap infrared radiation, causing the well-known "global warming" effect.
I'm sorry. You are no longer authorized to use Hunter S. Thompson as your avatar.
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