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Noctilucent Clouds Spread and Mystify
Wired has a feature on noctilucent clouds, once seen only at high latitudes but increasingly visible now lower down the globe. The clouds result from ice crystals at altitudes of 50 miles, higher than five 9s of the atmosphere. What water ice is doing up there, in a region 100 million times drier than the Sahara desert, is only one of the mysteries associated with the clouds. They are a recent phenomenon: the first scientific description of noctilucent clouds was penned in 1885. For a time it was believed that the clouds were an effect resulting from the eruption of the Krakatoa volcano two years before. Since 2002, the clouds have been sighted — and photographed — as far south as Oregon, Colorado, and Utah. Some scientists believe that human-caused climate change is playing a role, but others doubt this. Two satellites are in orbit to study the clouds; NASA's AIM generated this day-by-day movie of clouds in the vicinity of the North Pole during 2008.
Something else to handle the load of serving the movie:
http://drop.io/noctilucent
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"What water ice is doing up there, in a region 100 million times drier than the Sahara desert"
Bloody well isn't dryer than Mars and Mars has clouds and precipitation.
Before the chemtrail conspiracists show up. Somebody break out the Orgone generators!
Or maybe its just natures way of countering global warming..... you know like how evaporation helps cool....
If the hot water vapor left the planet, then the planet would be cooler and we'd have a water shortage to deal with. Otherwise, it's a closed system and there's no net change in temperature.
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Kinda disappointing that the first thing nowadays when people see something new it's that "Wow, humans really stuffed up the planet" instead of "Wow, that's an interesting natural phenomenon"
Your hair look like poop, Bob! - Wanker.
Otherwise, it's a closed system and there's no net change in temperature.
You know, except for that whole sun thing.
Sewage Treatment Facilities - "Our duty is clear."
APOD story
I blame gays.
Of course! There's only little fluffy clouds out there.
Aren't they caused by the space shuttle? I could swear there was an article a couple weeks ago on slashdot about it. Basically they found that they tend to form hours after the shuttle launch, particularly around Antarctica. The shuttle's boosters release X tons of water into the high atmosphere, at altitudes water can't regularly attain, which gets caught by high moving winds that drive it south, where they crystallize.
Interestingly enough we just had a shuttle launch just a couple days ago.
They went on forever - They - When I w- We lived in Arizona, and the skies always had little fluffy clouds in 'em, and, uh... they were long... and clear and... there were lots of stars at night. And, uh, when it would rain, it would all turn - it- They were beautiful, the most beautiful skies as a matter of fact. Um, the sunsets were purple and red and yellow and on fire, and the clouds would catch the colors everywhere. That's uh, neat cause I used to look at them all the time, when I was little. You don't see that. You might still see them in the desert.
It's neat because I used to look at them all the time when I was little.
Literalism isn't a form of humor, it's you being irritating.
The striped nature of the cloud features is probably because the data was gathered by the DMSP Weather Satellites using their low light detection sensors. These do not take a full-earth view of the world as the sun-synchronous GOES satellites do. DMSP vehicles operate in a lower orbit but a high angle and circular orbit. This brings them near the poles, and they cross the equator at roughly 9AM or 3PM locally to take advantage of the sun angle and shadows on clouds. They scan a wide path beneath them in visible and infrared channels, and have been used for years to do night light intensity mapping, such as for light pollution surveys.
The stripes are the paths from the several vehicles in orbit assembled over time when they passed near the poles.
Your tax dollars at work!
Pacifist paratroopers yell, "Ghandi!" when they jump.
Try my journal entry which connects noctilucent clouds to Space Shuttle launches and the Tunguska explosion.
Lets face it, if its getting hotter and dryer down here
Uh... it's not. Hotter, on average, yes (and, again, that's only on average, globally). But dryer or wetter depends a great deal on weather patterns and how they change. For example, Africa has seen a decades-long drought due to the rain belt moving. Meanwhile, the poles are predicted to see more precipitation due to higher levels of H2O present in the atmosphere.
If the hot water vapor left the planet, then the planet would be cooler and we'd have a water shortage to deal with. Otherwise, it's a closed system and there's no net change in temperature.
Water vapor sheds itself of heat through infrared radiation like everything else. It's radiated in all directions and the rays/photons/however you want to model them have a chance to strike something else and be absorbed on their way out of the atmosphere. Hot air rises and takes with it water vapor, which when it radiates its IR at high altitudes is less likely to heat other air.
Convection... it's not just for cooking on the cheap
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Well, not all mankind anyway. We know because of an incontrovertible nice looking graph that pirates keep global temperatures down. As pirates have declined, temperatures have gone up.
Meanwhile, most people don't have ships, so they do the best they can pirating music. Without the ships, parrots, and peg legs, they can't be as effective as sea pirates, so they have to pirate a lot of music (latest RIAA figure: 240% of all music is pirated). The number one hindrance to their diligent efforts to cool the planet before it's too late is the RIAA. So, the RIAA is responsible for global warming, QED.
One of the theories behind the correlation between the sunspot cycle and climate change is that the solar wind tends to deflect cosmic rays from the inner system, and that when sunspots are rare, the solar wind isn't as strong, which allows more cosmic rays to strike the upper atmosphere, generating clouds which deflect sunlight from the Earth. Since up until very recently there's been a sunspot drought, this might indicate a cause.
It's probably better to say that global warming was the getting out of the ice age. The climate got warmer, wetter, and less icy. The problem is we really have no idea what drove that global warming -- other than it was not the accumulation of greenhouse gases.
I complete agree with that. Even the most ridiculous global warming scenario can't begin to compete with a scenario where an ice sheet covers almost all of North America and global precipitation is decreased by 90%... something that has happened in the past, as regular as clockwork.
The biggest problem on the face of that theory is it says that the interglacial periods end because of a megastorm caused by certain conditions including "that the Earth be at or near perihelion...at the time of the northern winter solstice." Aside from the question of how that condition is going cause a megastorm, that condition happens on a 23,000 year cycle. A 23,000 year cycle is indeed contained in the ebbs and flows of glaciation, however, the interglacial periods (and the ends of interglacial periods and return of the glacial periods) happen on a 100,000 year cycle. The 100,000 year cycle corresponds to the change in the eccentricity in the earth's orbit... the one orbital parameter that should have the least impact upon the climate according to our (obviously flawed) understanding.
Hot and Wet. That's good when you're with a women, it sucks when you are in the jungle.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Or maybe, since temps have flatlined since '99
Temperatures have not flatlined since '99. That's simply a selective interpretation of the trend. The average temperature anomaly for '95-'99 was 0.468 degrees. For '00-'04 it was 0.572 degrees. For '05-'08 it was 0.665 degrees. How is that flatlined?
It's pretty clear on this graph.
"However, as long as there's a way to extract money from people by preaching AGW"
How much has it cost you personally?
"A warmer climate brings bigger harvests, providing more food to feed the legions"
Here in Australia the warmer climate has forced us into water rationing and cut our harvest in half compared to pre-1995 harvests.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
OOC, is it confirmed that Australia's issues are actually due to GW? Because, as I'm sure you already know, AU is supposed to have regular drought cycles as a consequence of the ENSO, as well... 'course, the one may very well be exacerbating the other.
..., such as glaciers melting (and yes, they truly are, worldwide, where I live here in Switzerland, but also in Alaska for example). I understand that there should be healthy scepticism at any scientific claim, but the climate is almost certainly changing, enough so that I can personally see it.
The climate is definitly changing.
As it always has been. Sometimes slower, sometimes faster. But in no way that should be an excuse to keep on polluting the planet.
bickerdyke