[Yo-Yo]

I live under a fairly major east/west flyway, and ever since I read about that study done in the days after 9/11 about contrail formation and the environment, I've been observing more closely. There are days that contrails last for 30 minutes or more, and there are days that contrails barely leave the aircraft before they dissipate. Then there are days that aircraft don't leave contrails at all.

Bogus subject, like most global warming topics, if you ask me.

[Proud2BeRight]

Just a lot of hot air.

[Lokibob]

Not really a bogus subject, but it affects us very little.

As the article said, the days after 9-11 were warmer, documented. I doubt it was that significant, tho. You could make the argument to keep cities from expanding (heat island) or a farmer from plowing his field.

Contrail formation is a function of temperature, pressure, and the amount of moisture in the jet fuel. As the temp gets colder, and the pressure is less (high altitude) the air can hold less moisture. A jet flys high enough, the water in the fuel condenses into a visible cloud because the relative humidity approaches 100%.

Programs exist today that can predict contrail formation. Do a google search using the term "skewt logp".

A simpler approach is to reduce the amount of moisture in jet fuel, IMHO.

In Fairbanks Alaska, when the temperature reaches 50 below, the automobiles create contrails, however, they call it ice fog, since it is on the ground.

[muir_redwoods]

I'm sitting inside looking at 14" of snow in my yard. It's going down to the single digits tonight on the good old fahrenheit scale and below zero tomorrow.

Would somebody please figure out how to speed up this global warming thing? It sounds really nice about now and, besides, I hear they're trying to figure out how to grow bananas in Georgia

[farmfriend]

Rights, farms, environment ping.
Let me know if you wish to be added or removed from this list.
I don't get offended if you want to be removed.

[BJungNan]

Oh good! Now the airlines are getting in on the global warming act to save themselves so money on fuel.

I knew this global warming was useful. I just never realized it extended beyond lining the pockets of those promoting it.

[ken21]

wha' happened to acid rain?

[AlbertWang]

I think science supports my idea of reducing global warming by introducing a shading effect from black particulates. In the 70's particulates of this kind were projected to cause world wide global cooling.

How do we do this? easy, burn tires. If every good environmentalist in this country burned just one LT235-15 each week could beat this thing.

I see "Burn-a thons" where we all gather in the park and light up a radial. The little kids could burn wheel barrow tires, the 5th graders could burn donut spares, etc.

[Outland]

"Bogus subject, like most global warming topics, if you ask me."

And you're absolutely correct.

Being the rabid long-time observer that I am of this "global warming" scam, I was going to write a long-winded, scientific but witty rebuttal to the posted article, but I declined since I didn't want to put anyone to sleep. Suffice it say, there are articles on NASA's own website based on the original article in Science that more or less claim that contrails don't make any significant difference. It seems that they can block sunlight as well as they can reflect heat, so the net gain is zero. NASA even goes as far as saying that cirrus clouds have a heat trapping effect where contrails have an opposite effect. Personally and scientifically speaking, I don't believe that contrails figure into the equation at all.

Worse yet is that the NASA article, this posted article and one by CNN conflict with each other on various levels. It's more evidence that no one knows what they're talking about... as if we didn't already realize that.