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Study: Jet Exhaust Affects Weather
An anonymous submitter writes: "Warp 10 speeds may affect... Ooops, wrong story.. Apparently, jets are affecting the weather and contributing to about a 3 degree daily temperature variation. Even a single degree variation in overall temperature (climate) is significant, but I'm not certain how significant is 3 degrees in local temperatures." We mentioned this before - there was a Wired story - but now their work has been published in Nature and the AP has picked up the story.
All the concrete in the airports have been doing this for years. Ever hear of urban heat islands?
This will only encourage the weird science crowd who are looking at the contrails as "chemtrails" and look at the whole thing as an effort to control global warming, or do other mean and nasty things.
Google reveals about 18,000 hits on the word "chemtrails" alone. Have a party.
"It is a greater offense to steal men's labor, than their clothes"
How can you derive significant results from 4 days of data? Silly...
Ok, let me see if I understand this....
.000000057% of the total data? I suspect that any competent statistician would laugh you out of his office if you asked him to attempt to calculate a trend with a sample that small.
According to most theories the earth is 3.5 billion years old. We (humans) have been measuring the temperature for less than 200 years. 200/3.5X10^12=5.7X19^-8. We are attempting to calculat trends in global warming with
"Like fire and fusion, government is a dangerous servant and a terrible master."~RAH
More worriesome is that jet exhaust probably contributes proportionally more to the greenhouse effect than the amount of pollutants realeased would indicate, as it tends to be dumped high up, resulting in more greenhous gases ending up in the ozone layer than it would have had it been burned close to the ground.
/Janne
Trust the Computer. The Computer is your friend.
Cell phones don't cause brain cancer. Does this mean researching the effect of high voltage power lines is a waste of time?
Lunatics believe that aliens visit earth on a regular basis to indulge their twisted ass fetish. When we look for evidence of martian microbes, are we just encouraging them (lunatics, not martians)?
This contrail weather effect is good science - the deviation they've identified in temperatures is statistically significant. Now, that isn't proof; statistically significant variations do arise by chance, and you can certainly get a stistically significant result that confuses the real causality (Less people Drove around Sep 11th, did that cause a significant local drop in CO2? Is this an incidental effect of overall climate change? So on and so forth.) However, just because it isn't proven, we can't dismiss it either (personally, I think contrails probably do effect the weather,) just because there are loonies who believe something similar.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
Ho my... We made how many measure on Electrons-positron anihilation ? How many measure on some weird galaxy outside ? How many skeleton do we have on prehistoric being ?
The amount of measure don't say anything about a model being wrong or correct. The problem is first to determine if the measure we did amount to correctly represent the whole "populaztion" we are measuring or not, second whether those are following the known modell or not.
Measure on 4 days are enough to establish a modell of temperature on variation of monthes or year. WE DO NOT care on temperature variation on geological scale for that study ("does jet have influence on local temperature or not")
Same pr9oblem with your reasonement on global warning. it doesn't matetr if we have a popualtion measurement on 0.000001% of the history of earth. We are effectively measuring something on the historicalö size (last 200 years) and that is what matters for our modell and sampling. We are trying to see if we influence temperature enough so that it becoems dangerous for US ("now"). Not that wetheter such warming occurs at slow geological scale. Who cares if temperature change by 10 grad celsius in 10 power 7 years, we are seing if we are generating the same change in 100 years...
Everything is a matter of sampling and scales. The aforementionned Competent statistician would mention it to you. Take a representative number of the population and you will have a good enough snapshot of the population (within error).
Now i am waiting for somebody with the infamous proverb "there are 3 types of lie : Big lie, DAmned lie and statistics".
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
A minor point, but important
anyone with even the smallest knowledge of scientific research can tell you that those results will never get published in any acientific journal
/. story, you'll see that this has /already/ been published in Nature.
'acientific'? Freudian pseudo double-negative?
If you read the article, or even the
To suggest that you can't learn anything from these situations reflects a misunderstanding about how science really works.
Absolutely, but where did I suggest that ?
My point was that there was *nothing* done to cancel out other factors or even explain how the numbers could have been affected. A real scientist would also have explained how the average of the same 4 days can change drasticly between years.
It is possible to skip the control group, sure. But in that case you have to repeat the experiment again and again, with and without the factor you are trying to measure (and you also have to include numbers from other factors), and then you calculate convergence for what you are trying to measure.
One measurement like this isn't worth piss, and yet it is presented as science.
echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc
You didn't even have to RTFA - the write-up itself says, "but now their work has been published in Nature." You know, the well-known scientific journal ?
Let me let you in on something...in investigations of the natural world - you know, that thing outside the lab? - you often don't get to have a formal control group. Cosmologists, for example, don't have a "control" universe to check against. Neither do meterologists have a "control" Earth to check against.
And if you had RTFA, you might see that what they were looking at was not the average temperature, but the temperature swing between day and night.
Saddest thing of all is that your post was modded up.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
I love the "3 days isn't statistically significant" crowd. They had 3 days with no civilian air traffic. They observed military cargo flights leaving contrails that over a few hours turned into very large cloud formations.
Weather satellites observing six separate instances of these contrail to cloud formation growths is significant. There were more, but they spotted six instances where one plane flew through a clear area and made a cloud formation. Thet's pretty clear. Take 3 days without vast airplane formed cloud cover and, using all the other days with the manmade clouds as a control group, you can spot a 3 day blip with temperature variations of 3 degrees celcius more than all the days before and all the days after.
We had a 3 day window with wider variation in temperature extremes. We had a 3 day window with negligible air traffic. We have documented how well one airplane can make cloud cover. I'm not a global warming person or anything, but if it looks like a duck, swims like a duck and quacks like a duck, then you've got an agenda of your own if you won't admit that we've got a duck.
Saying that air travel affects our weather isn't panic or tree hugging, it's observation. We're not going to stop flying. We are affecting things, for good or bad we don't even know. I don't know how we'll be able to tell- that's where this information is insignificant. The effects are obvious, but whether these effects are actually bad is not something we can determine yet, if ever. Who knows, maybe more research on jet propulsion can end up stopping this. different insulation, directed airflow, who knows? Just because we don't fully understand something doesn't mean it doesn't exist. We may not have to, or even want to change anything. We just don't know enough about it yet.
I spent a year in Iraq looking for WMD and all I found was this lousy sig.
So heating my home during the winter so I don't freeze has an environmental impact too. This is all so much alarmist bullshit. It's time people get used to the fact that as humans, anything we do has an impact on the environment and to get on with their freakin' lives. So are we going to forsake air travel now? Move to blimps? What impact do you think all the worlds ocean going shipping has? About the only people than can claim near total environmental unity are the various tribal segments of the world. The day you're willing to take a step backwards and live like that is the day I might start listening to this crap.
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The "researchers" did more than just compare weather reports:
However, instead of studying the lack of airborne jets during the FAA's three-day moratorium, Minnis considered the few aircraft that were in the skies -- military jets and transport planes.
In a usually packed air corridor around Washington, D.C., Minnis followed satellite images of a lone contrail drifting through the mid-Atlantic states on Sept. 12. The three days of grounded air travel provided him a unique opportunity to model the evolution of single contrails where normally scores or hundreds would be found.
He witnessed six contrails, each no wider than an airplane wing, evolve in a matter of hours into cloud banks that covered 20,000 square kilometers.
Yes, more research is required. Yes, it's pretty damn obvious that there is an effect. No, nobody knows if the effect is good or bad, but it is quite definitely there.
I spent a year in Iraq looking for WMD and all I found was this lousy sig.
At least somebody can admit the possibility. Humans causing global warming might be a plausible theory, but it won't be because any evidence presented so far, because any evidence presented so far is so damn thin it's pathetic.
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A more interesting study would be to stop all petroleum based engines for a month (including jets), and measure the impact on the climate...Alas, this will never happen, because people are addicted to their lifestyles.
Are you kidding? You're asking every single person in the world to roll back their technology over 100 years. How would ANYONE get around? It has nothing to do with addiction to lifestyle, it has to do with that technology being necessary for most people's LIVES, since so few people have any alternate means of transportation. Since the advent of the supermarket, corner markets no longer exist (sure, convenience stores exist, but have you ever tried to actually eat a meal from a convenience store that consists of more than chips and beer?). The majority of the population would have a hard time getting to and from a grocery store, typically located several miles from their home. For most people, walking that far would be an all-day proposition, or out of the question entirely. Not many people have a horse and buggy anymore, and a bike that isn't set up to carry a load is woefully inadequate to the task of hauling large quantities of groceries. Not to mention the fact that farmers wouldn't be able to harvest their crops without their petroleum-burning tractors, combines, etc, so even after your little experiment was over, people STILL couldn't eat. Few people would be able to get to work, since few people live within a short distance of their jobs (the car made suburbs possible). Do you consider natural gas- or oil-fired power plants to be petroleum based engines? If so, we wouldn't have much electricity either. In short, the economy would completely shut down, thousands of people would die, and your "interesting study" would have a disastrous effect on the world.
First, they're not actually talking about exhaust here, they're talking about contrails, i.e. condensed water (clouds).
Second, the contrails, don't contribute to a temperature variation, they prevent it: "the clear skies boosted the temperature swing between daytime highs and nighttime lows by about 3 degrees nationwide."
Third, to all those who say this is laughable statistical analysis, it is not. They studied the weather, not long-term climate changes. And in fact it is well known that on days with a clear sky, it gets hotter during the day and colder during the night. I'm sure everyone of you already noticed that. The clouds prevent the sun from heating up the earth during the day, and during the night, they prevent the heat from radiating into space. The only thing that had not been researched so far was the effect of the (small) amount of clouds that are artificially created by jets every day. Surprisingly, it turns out that these clouds have the same effect that other clouds have.
Relating this to global warming is just speculation. Contrails are basically just clouds, and I don't think reducing variation in temperature between day and night will contribute to or reduce global warming. That just doesn't make sense, it's like saying rainy days contribute to global warming because there are so many clouds. Now I'm pretty sure that jets do contribute to global warming, but that's due to burning fuel, not due to creating contrails -- they could just as well burn the fuel on the ground, causing no contrails at all, and it would contribute to pollution of the air.
Sig (appended to the end of comments I post, 54 chars)
The problem is that global warming doesn't take into acount the previous warming and cooling cycles presented via geology. And since you're waiting for it, I'll take the bullet and say that global warming is a case of "figures lie and liars figure". And since you're mentioning proper scale, .000000057% (or close enough) is a pretty damn small slice of history to be working with. Fact is we aren't going to have an accurate snapshot either way until you can find similar planets in various stages of their lifecycle, go back in time, or vastly improve geological research. And until one of those three criteria is met, global warming is not even an educated guess.
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I would hardly call Nature a scientific journal. It's more on the lines of Popular Science, except for biotech. If Popular Science was a scientific journal, damn, Sharper Image would rule the world. ;)
There is no increase caused by jets.
Unfortunately, the article submitter obviously didn't understand at all what the article says -- first, it doesn't say earth's average temperature increases or decreases, it says the daily variation, i.e. the difference between night and day, changes. This is something that you can very well observe with just a few days of data.
Second, the researchers claim that the jets reduce the temperature range.
Sig (appended to the end of comments I post, 54 chars)
Ok, picture this...
You have a plane flying around with a nuclear reactor on board. First, you have to keep it cool and dump the excess heat. Whether that'd be the equivolent to a coventional jet engine or more, I'm not sure, but you're basically coming around to the same problem. Second, you have a nuclear reactor flying around above peoples heads. Nevermind that you can make it damn near fool-proof and crash resistant (like nuclear warheads that'll withstand impacts the rest of the airframe won't), environmentalist propaganda would paint pictures of meltdowns in the sky and the scattering of nuclear material everywhere. The last reason alone will guarantee you won't see em in unclassified aircraft anytime soon. That, and about the only real advantage nuclear will gain you (after the signifigant increase in weight) will be endurance to stay aloft as long as the reactor provides power. An intresting point to be made would be that in a crash you wouldn't have to worry about a fiery impact scortching miles on end. Even if the reactor somehow "cracks", a 747 won't have as large a pile to draw power from. Sure, radiation would be a problem, but more than a fiery ball of death?
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ok i probably can't spell Dendracronology but
There have been studies of tree rings (Dendracronology) thousands of years old, the width of the tree ring tells you about the climate at the time it was growing.
So we have measured global tempretures back a few thousand years at least.
Then there's the ICE cores that can also tell you about global climate, they too go back thousands of years.
So you can say that in the past 50-100 years the climate has changed a stastically signifacant amount when compaired to the past 3-4 thousand years
failing that....
Rock strata can tell you somthing about climate going back 10's or hundreds of thousands of years.
thank God the internet isn't a human right.
It's you're call who to believe, and as to Bush, it turned out that those were elements of his cabinent who weren't authorized to make the statment, but that part of the story didn't see even half as much press. But don't believe me :p
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I guess I should cancel my upstart, Burrito Airlines.
Table-ized A.I.
When slashdot selected the same story just three short days ago, they also linked to an NPR story and a blurb on the nature website.
I'll one more, very important, link to the mix. You can read the abstract for free. Reading the paper itself is not free, unless you count going to your local university library for the dead tree copy as free. Before anyone else comments on the science behind this, please at least read the abstract, and hopefully have the knowledge to pass at least one introductory statistics course.
Slashdot is jumping the shark. I'm just driving the boat.
The depletion of the ozone layer is caused by the release of Chlorofluorocarbons (CFC's) used as refrigerants and aerosol container propellants, rather than the release of carbon dioxide through the combustion of fossil fuels, which causes the greenhouse effect. There is little connection between the two problems.
---- "If we have to go on with these damned quantum jumps, then I'm sorry that I ever got involved" - Erwin Schrodinger
... don't breathe.
Software Wars
There is a joke non-existing journal eften refered to in the scientific world, it's called "Journal of non-repeatable results", and belive me "Nature" is one such journal..
And if you had RTFA, you might see that what they were looking at was not the average temperature, but the temperature swing between day and night
Read carefully: the difference between day and night is greatly affected by skyes.. Skyes, during night, act as a isolator, and keep the heat from escaping into space.
Many skyes = Colder day & hotter night = less difference between night & day
Few skyes = Hot day & cold night = more difference between day & night
Add the effect from greenhouse gases and your "data" is worthless.
Trust me, 4 days of data is absolutely insignificant and those results will never get published in any scientific journal !!
echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc
??? Pardon me, but last tie I knew they had thousands.
Neither do meterologists have a "control" Earth to check against.
And that, my dear watson, is why the earth is not studied as one big rock, but as many small, where you have 'control groups'
echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc
This has been scaring the crap out of me for years! I've lost many a nights sleep fretting about the ocean rising, as it is. I don't know what to do but, its obvious that we've got to do something. And do it fast, we only have 1200 years before Miami sinks.
Oh bother.
Nature is probably the most highly respected jounal in all of American science, across every discipline. This is even more ridiculous than your previous claims.
On more reason to get off the fossil fuel habit.
Except that you're assuming this effect is negative, which is by no means clear. If global warming turns out to be a significant problem, increasing the impact of airplane contrails is one of the more interesting technical hacks that has been proposed to fix the problem.
The relevant patent can be found here: Stratospheric Welsbach seeding for reduction of global warming.
I play Nerd-Folk!
Read the article people! That 3-degree variation ended up LOWERING the temperature by 3 degress on account of air traffic, not raising it. So, if we're all worried about global warming, fly more!
Probably, you are referring to Greenland.
First, it is a common misconception that global warming means, it will be warmer everywhere. This is not true, especially for Europe (see Gulf-stream, effect of lower density due to molted ice on).
Second, Greenland (named by Erik the Red to encourage his people to settle there, after discovering that a name like Iceland was detrimental to it's publicity) is still green in some areas (and there are still glaciers, too)).
"Between strong and weak, between rich and poor [...], it is freedom which oppresses and the law which sets free"
Nature is a well-respected peer-reviewed scientific journal. So your assertation is simply not true.
As for the rest of your post, I can't find any defintion of "skyes" other than a chain of islands off of Scotland, so I have no idea what you're talking about.
Almost sounds like you're talking about clouds - but of course, the whole fscking point of this research is how contrails affect cloud formation which then affects local climate.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
You know, you might laugh about it, but if you lived somewhere where even a slight variation in sea level is of major concern, say Venice or Bangladesh, then I doubt you'd be so flippant about the issue.
/. stories that have an environmental slant to them have nothing positive to add to the debate and prefer joking about the subject rather than even admit that there might be a serious problem that needs to be addressed.
/. if not elsewhere, it's fashionable to be worried about the chances of the human race being wiped out by a giant asteroid collision but it's laughable to suggest that we (and countless other species) may be at danger because of our own reckless behaviour.
(Fact: Venice is sinking and many of its famous piazzas are frequently flooded. Fact: Bangladesh is under constant threat from flooding, which affects millions and kills thousands practically every year in recent history.)
I find it curious that a great number of people who comment on
If there was a small chance that toxic chemicals were seeping into your drinking water then you'd be mad to dismiss it so nonchalantly. If there was a small chance that your car's tyres were defective and could kill you then you'd be mad to ignore that too.
Similarly, if there's a small risk that your actions (together with that of the rest of the civilisation that you live in) was causing major damage to the ecosystem then you'd have to be a complete idiot to ignore the possibility.
Somehow, on
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
Nevermind that you can make it damn near fool-proof and crash resistant (like nuclear warheads that'll withstand impacts the rest of the airframe won't), environmentalist propaganda would paint pictures of meltdowns in the sky and the scattering of nuclear material everywhere.
Oh please. Even if the reactor is made 100% safe so that a skyscraper impact spreads no radiation, how do you prevent the plane from being hijacked and flown to an "axis of evil" nation that wants to get its hands on the plutonium? A nuclear plane could fly around the world many times without refueling, so this is an issue even for domestic flights. A nuclear-powered commuter flight from Boston to New York would easily be in range of North Korea. How are you going to guarantee that this won't be a problem? With computer-enforcement of no-fly zones? Or by arming pilots?
The tight export controls on a nuclear plane would be just one of the many headaches that an aerospace manufacturer would face, and while those caused by "tree-hugger" sensibilities are among them, there are many others. Ideology aside, safety and nonproliferation are serious problems that need to be addressed in any project of this nature. Nuclear planes are not cost-effective to manufacture. And unlike nuclear submarines, they do not solve any compelling problem that is left unaddressed by their conventional counterpart. Even the military, which comissioned the manufacture of nuclear submarines during the Cold War and was not as affected by "environmental propaganda", never did the same for the nuclear airplane.
The US was at a stand still thoes three days. Auto trafic was much lower as was industrial output (as well as industrial pollution) was down for those three days.
Maybe they didn't measures what they thought they were.
Now if life were to change such that cars were no longer economical or possible for some reason, i would look into moving or changing jobs. However for the sake of a one month experiment, no way.
And while i've heard that it's different in some other countries, in America at least without gasoline everyone who lives in a city or major suburbs would have to move. With out current infrastructure we don't have the means to deliver the food we produce to the people who eat it without petroleum products. Most people in cities or suburbs may be within walking distance of a supermarket, but it doesn't do much good if the supermarket doesn't have any food.
Sure we could fix all those issues, between alternate fuel supplys and alternate methods of transporation, but it's a bit too entrenched to be refered to as just a lifestyle. Whether or not i can go down to the mall and buy a cd or some new clothes is a lifestyle, the method by which the food necessary to my life is delievered isn't so much.
This Space Intentionally Left Blank
Christ, I get a troll mod, *and* get called stupid. You all *think* you need cars, and grocery stores, but you do NOT. - that is a period.
"we don't really KNOW what the temperature trends are from as little as 4000 years ago."
And we never will unless we invent a time machine. Just like we don't know what the temprature in pluto is, just like we don't know how far the moon is.
Sure we can never KNOW what happened in the past but we can make pretty damned good guesses. For a long time atoms were guesses. Nobody KNEW that atoms existed for sure. Nevertheless it was a well accpeted theory and it was right.
War is necrophilia.
Why does anyone need to 'get around'? Until the last 100 years, everyone basically remained in an area of a few square miles for most of their lives.
And before (nearly) everyone had a car, everything everyone needed to survive was within walking distance. Work, the grocery store, the drug store, the doctor, EVERYTHING. I live 12 miles from where I work. I live 4 miles from the nearest grocery store. I'm guessing here, but I probably live about 5 miles from my doctor.
Look at monkeys, and tell me I'm wrong.
You're wrong. Last I knew, monkeys lived within inches of their food. Humans did too, when we were all subsistence farmers or hunters. Now a lot of us live in cities. How much food do you see being grown within most metropolitan regions of the US?
I don't know about you, but walking a few miles to a store doesn't take all day.
No, it doesn't, for me and (presumably) you. But ask the average American (whose idea of exercise is to lift the remote off the table and walk to the bathroom a couple times a day) to walk 3 miles to a grocery store, then 3 miles back while carrying 30 pounds of groceries, and it could take a while.
you'd be forced to produce your OWN [food].
Now that's a funny thought. I live in a city. Where do you propose I grow this food? Where do you propose I get the seeds? Etc.
Those who can't care for themselves are already cared for by others, so the disabled and elderly have their bases covered for the most part.
Both my grandmothers are in their 80s, neither are cared for by others, and neither would be able to walk to the grocery store, let alone back with an armful of groceries.
Our society is not so unethical that in such an experiment, we would just abandon those in need.
No, but when I'm spending 8 hours a day at work, 6 hours a day walking back and forth to work, and a few hours walking back and forth to the grocery store, I have little time to walk 150 miles to bring my grandma groceries.
First, I didn't mention the world.
From your original post: A more interesting study would be to stop all petroleum based engines for a month. Since the US does not have a monopoly on petroleum based engines, I merely assumed you meant the world. I apologize.
Second, if my experiment came about from an uncontrollable event, you would probably be the first to die.
Ha. Not likely. I'm a backpacker, so I know my edible plants, and I'm in excellent shape. It's the fat ignorant slobs that mostly populate the country that I think would die.
Wow, that is quite a lot of research material.
Cloud formation is one thing and it's effects on climate is another. But have a look at the article:
for Their conclusion: Without jets or contrails, the clear skies boosted the temperature swing between daytime highs and nighttime lows by about 3 degrees nationwide
So the 'swing' rose, indicating less skies ? (more skies would have decreased the swing)..
What is the theory here ? "publish crap and get some money "
echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc
The rings from the oak may not be that good on there own, but when you take rings from different types of trees you can tell a lot about the weather for that year.
Some trees grow better when it's hot
Some when it's cold
Some when it's dry
etc.....
thank God the internet isn't a human right.
I can't seem to find it now, but I've seen a NASA picture (super high res color) of the Eastern Seaboard that was just COVERED with contrails.
l .htm
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Here's everything that I can find in 5 minutes, it comes close to showing what I saw once. (I swear it was from the Terra satelite, but I can't find it right now)
http://www.wrh.noaa.gov/Flagstaff/science/contrai
http://visibleearth.nasa.gov/cgi-bin/viewrecord?2
http://www.wrh.noaa.gov/Flagstaff/science/contrai
http://visibleearth.nasa.gov/cgi-bin/viewrecord?5
http://visibleearth.nasa.gov/cgi-bin/viewrecord?4
Ships put out an amazing amount of water vapour, and photos of the Western Seaboard have shown huge numbers of ship generated cloud banks off of San Francisco. Here's one example:
http://visibleearth.nasa.gov/cgi-bin/viewrecord?1
It's the fat ignorant slobs that mostly populate the country that I think would die.
and probably good eatin' too.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
Oopsie, hehehe.