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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.
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
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".
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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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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.
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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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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
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
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