Noctilucent Clouds Likely Caused By Shuttle Launches 132
icebike writes "In our recent discussion of the phenomenon of noctilucent clouds, there was some suggestions that these might be the product of global warming due to moisture being lofted high into the atmosphere. It now appears that these clouds are simply the product of Shuttle launches. In a story about the Tunguska blast, Science News says: 'Each launch of a space shuttle, which burns a combination of liquid hydrogen and liquid oxygen as fuel, pumps about 300 metric tons of water vapor into the atmosphere at altitudes between 100 and 115 kilometers. Soon after the January 16, 2003, launch of the shuttle Columbia, a liftoff that took place just after the height of summer in the Southern Hemisphere, noctilucent clouds appeared over Antarctica. Similarly, a widespread display of the night-shining clouds showed up over Alaska two days after the shuttle Endeavour blasted off on August 8, 2007. Previous studies show that in both instances those clouds included material from the shuttle plumes.' So, man-made after all?"
Re:See? Man-made climate change! (Score:2, Insightful)
Re:Um, first observed in 1887 - well before shuttl (Score:5, Insightful)
first noctilucent clouds mentioned in recorded history were in 1887
1887 was when the term was coined. It is impossible to say whether the phenomenon called "noctilucent clouds" in 1887 is the same phenomenon we see today. For example, Northern lights might qualify as "noctilucent" and may look cloudy to boot. It's important to distinguish the phenomenon from the terminology.
Please go read the article. (Score:5, Insightful)
While I suppose the summary could be read that way, the actual article is a little more clear on the distinction. That some other events also cause noctilucent clouds, while true, does not invalidate the premise of the shuttle also causing them.
So mod parent down. Bitch about inaccuracies in the summary if you want, but don't pretend they serve as meaningful parts of the discussion.
Re:Um, first observed in 1887 - well before shuttl (Score:5, Insightful)
Its also quite possible that the recent appearances of these clouds was caused by the shuttle launches dumping lots of water into the upper atmosphere, regardless of what has caused them in the past
Re:Um, first observed in 1887 - well before shuttl (Score:3, Insightful)
Such as from a volcano, which can reach into the stratosphere, not as high as the shuttle, but probably far enough. Or perhaps from the other direction, a (or many) comet burning up in the atmosphere.
Finally! (Score:3, Insightful)
Re:See? Man-made climate change! (Score:1, Insightful)
Normal: Things we have observed for a long time. Not normal: Things we have observed only recently.
Since global warming is the main change currently happening to our climate, attributing other changes to global warming is often an acceptable first hypothesis, at least if there's a known mechanism that could potentially link the two.
Re:Um, first observed in 1887 - well before shuttl (Score:5, Insightful)
Causing, or contributing? (Score:4, Insightful)
Re:See? Man-made climate change! (Score:3, Insightful)
Someone had to say it. I wish CmdrTaco would write a bot which automatically inserts the "Correlation is not causation" thing into every discussion, along with an automatically selected XKCD cartoon.
Re:Why now? (Score:4, Insightful)
An obscure topic of meteorology, that appears to occur naturally from time to time, being correlated with space shuttle launches? And probably with a significant delay between release and formation of the clouds, one would think. I think you vastly overestimate the degree of weather observation that actually gets done, and our understanding of the weather system. Yes, there's much ground-based data of temperatures, precipitation and cloud cover but very little on the actual conditions up there - the lone weather balloons they used to send up don't amount to much. It's really only in the last few decades of satellites we've been studying it in detail.
In any case, I'm sure this will be used as another "disproof" of global warming. Like with Darwin when he gets 95% right and 5% wrong people always want to pretend that theories are either perfect or completely wrong, even though that makes no sense. Or assume some irrational assumption of uniform effects, so the results can violate them. Mess with say the Gulf stream and everything from Mexico, eastern US and Europe could get colder even during a global warming. Sometimes I wonder if they don't understand or if they just pretend not to...
Re:Carbon credits for shuttle launches? (Score:2, Insightful)
That's kind of like saying gasoline is more flammable than wood.
As infrequent as shuttle launches are, the relatively tiny amount of water vapor they've released is almost certainly not a significant contributor to global warming. There's just not enough quantity there.
But if somehow a *lot* of water got up there, enough to form a continuous layer from the equator to the poles, you'd be looking at world-wide year-round subtropical temperatures, not much temperature change from day to night, very little convection and thus no significant wind, and probably the only rain would be directly above bodies of standing water.
Humidity would achieve world-wide equilibrium, so there'd be no deserts and no rain forests, not to mention no glaciers. Pretty much the entire land surface of the world would be inhabitable.
Talk about terraforming!
We have easily enough water to do this. It's just a matter of how to get it up there.
Re:Cognitive filtering (Score:2, Insightful)
Secondly, What is the effect of noctilucent clouds on on our atmosphere? Is it clear? Could they be protecting us/earth from some solar radiation? Or are they having the opposite effect (increasing the greenhouse-effect, and/or reflecting more solar radiation into our atmosphere)?
Idea: Nanoparticles (or other charged dust) blasted beyond the stratosphere that we can control! Keep it where it can block the sun, occasionally produce festive light shows, and keep the alien's from reading our collective thoughts!
Re:See? Man-made climate change! (Score:2, Insightful)
Actually they weren't right because they said it was due to global warming. But what I don't get is that they are "scientists". They use the "scientific method". All their conclusions are "peer reviewed". They are smarter than all non-scientists. How could they be wrong? And if they were wrong about this is it possible that they could be wrong about other statements of "fact"? I thought scientists couldn't be wrong? That is was impossible for a non-scientist to question their conclusions?
Could it be possible (stay with me on this one) that they are full of shit and should be taken with more than just a grain of salt?
Re:Cognitive filtering (Score:3, Insightful)
Now, drag out all the charts, graphs, and politically-motivated reports you want, for and against; the only actual modern large-scale experiment that gives us any proof regarding human impact on temperature was the week after 9/11.
It was three days. Citation with reference here [realclimate.org].
The complete lack of aircraft over the US had a SIGNIFICANT effect on high and low temperatures immediately.
Three days is far too short a time period to say anything conclusive about climate. You might as well argue that the sustained low temperatures last winter are a sign that the world is cooling...
Couple that with this current evidence that a single shuttle launch can apparently impact cloud formation over the Antarctic, and I'd say that's a far-more-tangible red flag than the supposed connections made over CO2 or other 'global warming' gases.
So why isn't there a significant, sustained effort to minimize air travel?
You mean like this [yahoo.com]? Judging from this and the rest of your comments, you really need to get out more...
Re:See? Man-made climate change! (Score:3, Insightful)
A Hint: It's the increasing incidence of the clouds that is being "explained" by increased water vapour from rockets. Rockets obviously don't explain 19th century occurences of the phenomena recorded just a few years after Krakatoa (1883).
A Clue: You will get a better response if you attempt to debunk something that is actually being claimed. It's a bit disconcerting when you attack the nonsensical thoughts you project into other people's heads.
Re:Um, first observed in 1887 - well before shuttl (Score:2, Insightful)
Re:Cognitive filtering (Score:3, Insightful)
So why isn't there a significant, sustained effort to minimize air travel?
Because we like air travel and hate industry. Minimizing air travel would inconvenience too many of "the right kind of people."
The same kind of thinking can be seen in the summary: "It now appears that these clouds are simply the product of Shuttle launches." The key word here is "simply", implying that there's nothing to worry about, because shuttle launches are a Good Thing.
AGW may be real--the signal in ocean heat content is pretty damned interesting, if maybe not quite compelling--but the argument around it is almost entirely driven by social engineers who want to use the non-zero risk of a civilization-ending climate event to empower themselves and their friends.
Re:Causing, or contributing? (Score:3, Insightful)
That's an interesting point. Similarly, I wonder if the conditions that NASA chooses to launch during are related to conditions that allow noctilucent cloud formation.
Re:Cognitive filtering (Score:3, Insightful)
Considering how variable the weather is in September, how can you be sure you're seeing causation, and not mere correlation? Having 3 or 4 days of temps significantly warmer or cooler than the week before is normal that time of year, as it's when winter fronts start moving across the continent.
While I've seen the sky completely haze over between morning and afternoon due to contrail spreading (if you work outside all day and can watch the sky, you can see this happen) I'm still not convinced it's significant. How much of the moisture was already there, and condensed due to the air disruption??