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Zapping Contrails With Microwave Emitters
An anonymous reader writes "Dissipation of contrails with a powerful microwave beam aligned behind aircraft engines is being touted as a possible solution to help address air transport's effects on the climate. 'The remote heating of condensation nuclei could be achieved by applying electromagnetic radiation, such as microwaves,' says Cranfield University's Frank Noppel. 'Depending on assumptions made, calculation shows that the power required for such a device could be as little as 0.1% of the engine power.'"
My understanding was that contrails contribute to global dimming and are helping to keep temperatures down. If I read the article correctly, this would not remove any pollution, just remove the clouds and allow temperatures to be even higher. Reading it made me think that the goal has become to have no impact on climate at all - positive or negative. That doesn't seem right, so I think maybe I'm missing something.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
If this technology gets put into use, conspiracy theorists will start asking why they are covering up the contrail activity. Unless the "chemtrails" are not susceptible to microwave heating dispersement, then they will have something else to point at. I initially thought this was an article about a device to combat chemtrails being developed by said conspiracy theorists.
It will be interesting to see if a trend develops of pre-cooked birds falling from the sky behind jetliners outfitted with this technology.
Ignorance is Bliss -- And the Opposite is True -- Genius is Madness
http://news.nationalgeographic.com/news/2006/06/060614-contrails.html Aircraft are believed to be responsible for 2 to 3 percent of human CO2 emissions. Like other high, thin clouds, contrails reflect sunlight back into space and cool the planet. However, they also trap energy in Earth's atmosphere and boost the warming effect, the study says. (See National Geographic magazine's "Global Warning: Signs From Earth.") Stuber and other scientists believe that the effect of the contrails is significant. "On average the greenhouse warming effect dominates [the effects of contrails]," said Stuber, a meteorologist at England's University of Reading.
The stories and info posted here are artistic works of fiction and falsehood.
Only fools would take it as fact.
Although this seems interesting I think the airline industry has other more pressing worries. The current financial market has pretty much guaranteed that they can do nothing "green."
If our elected representatives no longer represent us, do we still live in a Democracy?
Reduce the atmospheric warming effect of contrails by microwaving and thereby heating the atmosphere...
Dare I say...BRILLIANT!
Actually, I wonder what effect this would have on those pesky naturally occuring clouds...
-=Bang Bang=-
WHY, in this age of "Global Warming will DESTROY the Earth" are they wasting money and effort on a way to get rid of contrails... something that is keeping us just a little bit cooler?
Drop the solar input on a farm by a couple of degrees, and the crops don't grow as profitably. It's the same for wind power-- some downwind agriculture fear that if turbines take energy out of normal wind patterns, their farms output will be upset measurably. Remember, Global Warming is not about short-term local conditions but about overall year-round global averages. Some areas will be colder, some areas will be hotter, and chaotic conditions will be stronger. Contrails affect local areas and should be more sum-zero.
However, as an aerospace company kind of guy, I don't think carrying heavy megawatt microwave emitters up to 36000ft and then burning MORE fuel to power them is going to be the answer to contrails.
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http://www.pbs.org/wgbh/nova/sun/contrail.html
Another study that took advantage of the grounding gave striking evidence of what contrails can do. David Travis of the University of Wisconsin-Whitewater and two colleagues measured the difference, over those three contrail-free days, between the highest daytime temperature and the lowest nighttime temperature across the continental U.S. They compared those data with the average range in day-night temperatures for the period 1971-2000, again across the contiguous 48 states. Travis's team discovered that from roughly midday September 11 to midday September 14, the days had become warmer and the nights cooler, with the overall range greater by about two degrees Fahrenheit.
These results suggest that contrails can suppress both daytime highs (by reflecting sunlight back to space) and nighttime lows (by trapping radiated heat). That is, they can be both cooling and warming clouds. But what is the net effect? Do they cool more than they warm, or vice versa? "Well, the assumption is a net warming," Travis says, "but there is a lot of argument still going on about how much of a warming effect they produce."
a possible solution to help address air transport's effects on the climate........ so the "a possible solution" to those little white trails behind jets that usually dissipate quite quickly is to shoot a powerful microwave beam in the sky. What could possibly go wrong?
I'm an American. I love this country and the freedoms that we used to have.
I thought we weren't meant to put metal in the microwave.
If the targeting was off just a bit wouldn't this be a little bit bad for the occupants?
However, having pre-cooked birds falling from the sky would help with feeding the family.
liqbase
Passenger: My $8 cilantro-turkey-roll-lettuce wrap is cold!
Flight attendant: Sir, we heated it in the microwave, but by the time we reeled it back in, it had cooled down to 30-below. Would you rather have the $9 Pepperidge Farm cookie?
Was not disappointed.
Definitely not an aberration. DEFINITELY.
-=Bang Bang=-
"Microwaving Contrails" would be a good name for a rock band...
Proverbs 21:19
calculation shows that the power required for such a device could be as little as 0.1% of the engine power.
A 747 uses four RB211 engines (or the Pratt & Witney equivalent) each of which puts out 30 megawatts of power. So this microwave contrail zapper is going to be using 120 kilowatts of power? That's 60-80 kitchen microwaves running simultaneously. That's more power than many radio stations use to transmit. I can't help thinking this will cause more problems than it solves. How is it going to affect radar, TV, cell phones, etc? How is it going to affect other planes on the same flight path? How is it going to affect the moisture already in the air? What's going to happen when one of these aircraft come in for a landing and forgets to turn off their contrail zapper?
It's probably money a lot better spent trying to build cleaner burning engines in the first place.
When our name is on the back of your car, we're behind you all the way!
Jet contrails apparently serve to cool the Earth during the day, as they reflect solar radiation, while at night they serve to warm the Earth, by trapping heat. So for maximum effect, you'd want to only dissipate the contrails created during nighttime flights. This would include not just "red-eye" flights, but air cargo operations like FexEx. Measurements taken during the grounding of all commercial flights following 9/11 indicate that there was a two degree increase in the range of day/night temperatures, so elimination of just the nighttime contrails could lower temperatures by a degree or so.
http://archives.cnn.com/2002/TECH/science/08/07/contrails.climate/index.html
Nothing for 6-digit uids?
My first expectation was something for bomber jets to make them less visible. I'd be surprised if it doesnt get ported over.
Remember how in Sim City an airport would dramatically increase pollution for your city? Yeeeeeah, it isn't far from the truth. Airports aren't transportation hubs; they're giant kerosene burners, which is why the air absolutely stinks for miles around. I seem to recall reading that one 747 during takeoff creates more pollution than a Toyota Prius will in its entire serviceable lifetime. Obviously you can't use microwaves at any kind of intensity during taxi, run-up, or takeoff, as the ass end of the plane is facing near or at the ground.
Also, it's pretty famous now, but someone studied the weather records around September 11th, 2001 and found there was a remarkable change in the weather across the country and in fact much of the world on the few days that followed where there was very little in the way of air traffic (and another change back to "normal" when air traffic resumed.) Ask most people and they remember it being rather nice out. I remember the weather in lower NY was absolutely spectacular for several days- beautiful blue skies like I'd never seen before in that part of NY.
Please help metamoderate.
And be done with it, Spiro Agnew's headless corpse agrees with this plan.
Grrrrrrrrrrrrr
Tsukasa: All I really want, is to be left alone...
Aren't contrails supposed to dissipate naturally in the first place? If you look videos of contrails during WWII, they would completely disappear within a minute or two because they are condensation (water) trails. However, some of the planes nowadays leave trails that last hours, sometimes a good part of the day. On top of this, they seem to be able to start and stop these trails on command, lots of pictures and looking up in the sky will show you this. So they want to dissipate these chemtrails now?
Even with lonbg-range microwaves, it'll just recondense since it lost the engine turbulence.
I'm only a second year in Aerospace, so I could have this wrong, but: Why implement a device that has significant mass, and requires a "large" amount of energy? The whole point is to reduce emissions, not create them. As I understand it, condensation trails are caused by low pressure areas formed by the wing tips/ends. Is there nothing that could interrupt the formation of low pressure pockets at the rear of the plane? I am aware that pockets of air can help aerodynamics of the jet. (Same principle behind golf-ball dimples.) Is there no middle ground?
Just wanted to note that I experienced the same thing, but have a couplre observations:
Do you recall the weather on 9/10/01 and the morning of 9/11/01? Absolutely gorgeous, nice shore breeze so we had clean air, sunny, and low humidity. I'm not sure if the weather subsequent to 9/11 was part of the same weather pattern or not, or how much impact reduced air traffic had.
Second, not only were planes grounded, but factories were closed, there was much less vehicular travel, etc. I think the grounded planes helped a but, but I imagine the reduced ground traffic was what really improved the air quality in and around Manhattan (downwind of the WTC excepted, of course).
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
It would seem the obvious reason for implementing something with such dubious prospects is to firmly eliminate one of the nasty conspiracy theories/rumors that circles around the drain of the Internet. Chemtrails.
These are supposed to be something that results from introducing various chemicals to either the jet fuel or into the engines themselves to make for a more docile population. Or to stir things up and create race riots which can then be brutally put down. Or some other result which often the people believing in this can't articulate.
The idea is there is some observable difference between a "normal" contrail and one of these "chemtrails" which stay around longer or appear more dense.
Is it worth millions of dollars to stamp out this bit of nonsense? I'm not sure. If you do some searching you might find out the extent of this is larger than you would have ever believed. And maybe it might be worth millions to get rid of it.
I seem to recall reading that one 747 during takeoff creates more pollution than a Toyota Prius will in its entire serviceable lifetime.
Let's not compare apples to oranges.
A 747 can carry up to 660 passengers in a single-class configuration. That's 132 priuses full of people.
To drive from NYC to LA is 2,791 miles. Repeating that drive 132 times will put 368,412 miles on your odometer. Although I'm sure the Prius is a very reliable car, it's unreasonable to expect any vehicle to last that long without a major overhaul.
TFA quotes a 1999 article regarding effects of contrail cirrus on climate. That was, of course, theoretical. Due to the few days of no planes above the US following 9/11, we have clear climatological data regarding contrails. Contrail cirrus serves to reflect daytime sunlight back upwards, and night time terrestrial heat radiation back down, the net effect being to reduce the variance in temperature changes over time.
There is no reason to waste aircraft fuel running microwave generators to ameliorate an effect which is not a problem.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Perhaps the military see it as a possible solution to reduce contrails on fighter jets?
Stealth aircraft aren't any good if they leave a visible contrail behind ;) (Actually I'm not sure if/how they've dealt with that on current stealth aircraft?)
Hello! I'm a disaster waiting to happen!
I think having a microwave emitter on kinda gives away your plane nowadays. WW2 had very basic RADAR, if the faction had it at all, so combat was visual. Turning on a microwave today (where combat also happens outside of visual range) is like turning on a big illuminated sign saying "Shoot a RADAR tracking missile up my tailpipe".
I cannot vilify Gore anymore when he flies to his latest Global Warming conference because by using his private jet he is helping save the planet?
arrggghhh!!!
* Winners compare their achievements to their goals, losers compare theirs to that of others.
It's not that complex. You just need to remember the implications of earlier experiments.
It's all about the information. And what we do with it.
Can't remember who precisely did the research, but I was watching an old Nova documentary yesterday about global dimming, and apparently by measuring the difference between daily highs and lows over the days surrounding 9/11, the days immediately after had a significantly smaller temperature range than the others. This was supposed to be a good indicator there was an effect on the weather, because the range trends usually change gradually. Interesting stuff.
98% of America's teens drink alcohol, smoke, and have sex. Put this in your sig if you like bagels.
Or we could vaccinate them after first microwaving them for safety. It's pretty clear that these contrails need be classified as terrorist clouds.
My parents ran a taxi for just over 300,000 miles. That was a pretty reliable car (Peugeot 405 diesel, can't remember the year but would have been early to mid 90s) but 250,000 miles wasn't unusual for them. I don't think it had many major overhauls in its lifetime, when you're running a taxi it's best to buy the most reliable car you can find new and then run it down to scrap. You don't even bother with dealer servicing, you get a trusted mechanic who can do things cheap.
These are UK miles though, don't know if they're different to USian miles.
Nick