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Thermosphere Contraction Puzzles Scientists
The thermosphere layer of earth's atmosphere begins 80 to 90 kilometers above the surface and extends several hundred kilometers into the sky; it is the home to numerous satellites and the International Space Station. It is known that the thermosphere occasionally cools and contracts, but a recent study of satellite orbital decay (due to light atmospheric drag) found that the contraction during 2008 and 2009 was significantly more severe than expected, leaving researchers at a loss for how to explain it. From Space.com:
"This type of collapse is not rare, but its magnitude shocked scientists. 'This is the biggest contraction of the thermosphere in at least 43 years,' said John Emmert of the Naval Research Lab, lead author of a paper announcing the finding in the June 19 issue of the journal Geophysical Research Letters. 'It's a Space Age record.' The collapse occurred during a period of relative solar inactivity — called a solar minimum from 2008 to 2009. These minimums are known to cool and contract the thermosphere, however, the recent collapse was two to three times greater than low solar activity could explain."
yay?
global warming. It's called "climate change" these days. Understand climate change and you will learn why our globe is spinning out of control and life as we know will soon be over.
It's Bush's fault.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
So now CO2 causes cooling too. Can't win.
The first 4 comments show as much.
The sky is falling in... literally!
"Don't worry, it's cool."
"Don't worry, I suffer from a bit of shrinkage, too."
On the one hand, it's reported this is not rare. On the other hand, we've got plenty of sensationalistic language: "significantly more severe", "researchers at a loss", "collapse", "its magnitude shocked scientists".
So, is it the usual news cycle hype reporting on a puzzling phenomenon, or is there a reason to be alarmed?
I was hoping for some comment that might shed some (presumably ionising) light on this issue, since TFA offers no suggestions. Instead, we have a series of boring troll posts.
Oh well, I'll just move on, nothing to see here...
CO2 is denser than air so naturally the atmosphere compacts under gravity as the density increases.
No sig today...
The sky IS falling. Oh, Chicken Little, how we all should've listened!
Over-the-top Response Guy! Giving "Over-the-Top Responses" since 1970.
Actually it's likely related to global warming, since CO2 emits light at a different wavelength than it absorbs it, it sometimes causes the thermosphere (and other layers) to cool and contract by the time the light gets to the outer layers. There are climate models that predict this. The heat is absorbed at low altitudes and not emitted at high altitudes.
Actually I just made that up, but it sounded good, didn't it? Right? I'm sure we can blame it on pollution somehow.
Qxe4
Global warming sucks
It's due to the lack of USB support in linux, the flaws in GPL, global warming, Barack Obama's personal war, and the terrible new changes to slashdot.
So, uh, what happens when the thermosphere contracts too much? The ISS goes *crunch*?
"It's called "climate change" these days. Understand climate change and you will learn why our globe is spinning out of control and life as we know will soon be over."
Just... go fuck a goat, you pessimistic bastard. What we don't need is people who are going to sit around and bitch about how we're all inevitably doomed. Those people (and you specifically) aren't a part of any solution, so yes - go fuck a goat.
My post isn't going to get any more insightful. You can stop reading now. We'll figure out the answers without you, goat fucker.
"...that I'm wearing a coffee pot for a cup?"
Okay, either that's one seriously underutilized coffee pot, or you're the greatest man on earth.
I wonder that the Amateur Radio low power operators have to say about the "skip" signals? That is when a radio wave gets caught in a "corridor" up there and "bounces" in there a long way before coming back to earth. The compression should have some sort of effect on them.
It's the sound a slam dunk makes.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
It is an interesting to me that the HAARP project was brought online a year before these severe contractions of the thermosphere. Although I'm sure the conspiracy theories are over the top, it would probably be dumb to disregard the fact that there are no other explanations right now as to what is happening to the atmosphere, but during this time period the military just happened to conduct an experiment against it.
I find putting "Mao eyes" is more appropriate.
The reasoning goes like this: if there is something about the temperature of the atmosphere that's in some sense unexplained this means scientists know nothing about the climate which means anthropocentric global warming does not exist which means my BP stock will keep its value and I will not have to sell my SUV.
Interestingly, global warming does cause colder winters. The cause of those colder winters is the melting of the ice caps.
More heat in the atmosphere means more energy, which causes stronger winds and quicker circulation. Cold air from the north pole travel faster to Europe and therefore has less time to warm in the way.
Those colder winters are more than balanced by hotter summers, we are spending away our ice reserves. It's like when you spend more than you earn. Your having more money to spend does not mean you're getting richer.
http://rs79.vrx.net/opinions/observations/significant/2010/environment/
Need Mercedes parts ?
when the contractions are 5 minutes apart
I wonder by which definition you say the Arctic ice cap is in "decline", but not melting?
The Antarctic ice sheet is shrinking, not growing. It's losing volume, which is the only significant definition of size when one considers climate issues. It's losing volume the only way a polar ice cap can lose volume, by melting. But, of course, you'll never know this if you have only one news source.
Warmer oceans cause increased water evaporation, which then precipitates as snow or rain. Considering that a large part of Antarctica is still well below freezing point, it's only natural that *some* regions of Antarctica have had more snowfall caused by global warming. Yes, global warming does cause both more snowfall and colder winters. Which is more than offset by hotter summers and increased ice melting.
"To calculate the collapse, Emmert analyzed the decay rates of more than 5,000 satellites orbiting above Earth between 1967 and 2010. This provided a space-time sampling of thermospheric density, temperature, and pressure covering almost the entire Space Age."
Personally when I see something I cant explain I suspect my data, algorithms or process. It would seem far more likely that there is a flaw with some element from which the thermospheres depth (height?) has been inferred than a sudden inexplicable contraction, I would have thought.
Of course the thermosphere is different. How many different universes have been in since they tried to turn on the LHC last year? There has to be something that is different to prove that we live in the one universe in which the LHC does not destroy the earth. Only real explanation.
21st Century Renaissance Man
Give it a break; it was just in the pool.
Wow, not even a blip in time and this is suppose to be significant? Haha
All the republican hot air for nearly a decade suddenly halted when Obama took office. This created an entropy vaccuum and hence the thermosphere cooled in order to fill the vaccuum.
i have been saying this for quite some time but hasn't anyone paid attention to the fact that hydrocarbons produce more water than carbon dioxide? methane is the most extreme example with a 2:1 ratio no hydrocarbon burns with less than a 1:1 ratio (fully hydrocarbons made of all double bonded carbons would be 1:1, obviously triple bonded, like acetylene, is the only exception).
it seems logical to me that increased atmospheric water is going to mean a rise in atmospheric density (possibly also increasing total internal reflection and reflection) and obviously also a lowering of overall temperature in the atmosphere (more water in the atmosphere means a higher latent heat capacity). increased density means more effect of gravity, as well as the overall drop in ambient temperature from increased heat latency.
i'm not sure what other effects there would be from increased atmospheric water, as well as increased CO2 and reduced O2. i was thinking it may influence cloud formation patterns, alter the amount of overall radiation striking the poles and equator (via total internal reflection caused by increased atmospheric refractive index).
in any case, i'm not that familiar with climate modelling and i'm not sure how much they count the increase in H2O in the atmosphere in their predictions, but it seems to me if we are gonna go out hunting for human influences on climate changes, then the influence of water should be, in my view, rated more highly than any other factor because of the refractive index and latent heat capacity of water, two factors that are naturally going to give it the strongest influence of any chemical in the air.
The temperature of the thermosphere has nothing to do with the temperature of the climate. We're talking about the part of the atmosphere where the international space station orbits. The rules there are very different from the lower atmosphere (as are the temperatures (up to a few thousand C depending upon where you are). The temperatures are controlled by the absorption and emission of radiation (and, of course, conservation of energy).
The radiation absorbed by these tenuous gasses is in the extreme ultraviolet and soft x-ray. We've been monitoring the solar EUV and SXR output for quite a while. When they are high the thermosphere heats up and expands. Satellites in low orbit experience a lot of drag and end up in lower orbits. Because of the extended solar minimum EUV and SXR are way down, but they haven't changed enough to explain the entire temperature difference. So the remainder of the difference has to be in the emission of radiation in the thermosphere. There's a series of linked partial differential equations involved, so I won't do the actual math. But the easiest way to cool the thermosphere is to add higher amounts of species that have a lot of cooling transitions.
One of the people quoted in TFA thinks it might be due to increased CO2. I have a hard time buying that. Because it's heavy, it's hard to get CO2 into the thermosphere. It would be tough to get an in situ measurement of CO2 and it's ionization products with any existing instrument
As far as what this effect could do to the world. Well, it could screw up your AM reception. And it could screw up a prediction of a LEO satellite's orbit. (i.e. your sun synchronous polar orbit might not be as sun synchronous as you hoped.) But it's not going to kill dolphins or sea turtles, or cause earthquakes or polar shifts.
I could do the required measurement with an FUV to NUV spectrometer for diffuse radiation on 2-axis coarse pointing gimbal. I'd need a satellite for a platform. But by the time I got it built and launched we'd be heading up toward solar max.
Disclaimer, I do this for a living.
Support SETI@home
Its probably due to MS's lacking the ability to combat the IPAD and IPHONE from Apple. MS is sucking up all the available oxygen to try and come up with a real product for anything.
The Global Financial Crisis - no one could afford a Thermosphere.
My ism, it's full of beliefs.
Did anyone else think of the giant vacuum in Spaceballs when they read this article?
Proof!
Also Hitler.
So I'm confused... you are saying that something with more mass / more potential energy is "colder" than something that has less mass / potential energy?
Wouldn't the temperature per molecule go down?
How much is your data worth? Back it up now.
NVM.
The ratio would stay the same, I get that.
How much is your data worth? Back it up now.