What does temperature in mesosphere mean?

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SUMMARY

The discussion centers on the temperature in the mesosphere and its implications for human perception and measurement. Participants clarify that despite high temperatures, the extremely thin air results in minimal thermal transfer, causing the air to feel cold to humans. The temperature is defined as the average kinetic energy of air molecules, which can be high even when the air density is low. This leads to a paradox where temperature readings in Fahrenheit and Celsius may not accurately reflect the thermal experience of objects in contact with the mesosphere.

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  • Understanding of atmospheric layers, specifically the mesosphere and thermosphere.
  • Knowledge of temperature measurement and its relation to kinetic energy.
  • Familiarity with thermal conductivity and heat transfer principles.
  • Basic grasp of the physics of gases and their behavior at different altitudes.
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  • Research the properties of the mesosphere and its impact on temperature perception.
  • Learn about the measurement techniques for temperature in low-density environments.
  • Explore the relationship between kinetic energy and temperature in gases.
  • Investigate the effects of altitude on thermal conductivity and heat transfer.
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Atmospheric scientists, physicists, educators, and anyone interested in understanding the complexities of temperature in different atmospheric layers.

jostpuur
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I tried to check some atmosphere stuff from here: http://www.srh.noaa.gov/jetstream/atmos/layers.htm

It says

However, despite the high temperature, this layer of the atmosphere would still feel very cold to our skin because of the extremely thin air. The total amount of energy from the very few molecules in this layer is not sufficient enough to heat our skin.

I thought that the temperature is by definition a quantity which always becomes equal between materials which are in physical contact. So if a human body would get cold in the upper mesosphere, doesn't it mean that the air is cold there? Furthermore, if a human body gets cold there, don't temperature gauges get cold too? How are those high temperatures even measured?

update:

I already got one idea. The page explains the reason for high temperatures to be this:

The gases of the thermosphere are increasingly thinner than in the mesosphere. As such, only the higher energy ultraviolet and x-ray radiation from the sun is absorbed. But because of this absorption, the temperature increases with height and can reach as high as 3,600°F (2,000°C) near the top of this layer.

Does this mean that we should consider the system, consisting of both the electromagnetic radiation and the air molecules, to be the system which is in a high temperature? And if a human goes out there and doesn't protect him or herself in a shadow, he or she will get fried?

update 2:

I don't believe that the idea of the first update is the solution to the problem. A better sounding idea is presented in the post #7. Although the frying effect of the sun's radiation is probably notable too.
 
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I think that in this case they're referring the average kinetic energy of the molecules as temperature. If so, the temperature can be quite high, but the thermal transfer to another body would be minimal because of the low population of molecules.
 
Danger said:
I think that in this case they're referring the average kinetic energy of the molecules as temperature.

But they give the temperature in Fahrenheits and in Celsius. Those numbers must have some quantitative meaning.

If so, the temperature can be quite high, but the thermal transfer to another body would be minimal because of the low population of molecules.

This is a paradoxical statement, which IMO doesn't take into account the correct meaning of the terminology. If I understood this point correctly, this message should be said like this: "The average energy of the air molecules is high, but the temperature of the air as whole is low".

update:

I immediately understood another possibility. Did you mean that the temperature of the air is high, but the thermal conductivity is low? But that doesn't make sense really either. If the thermal conductivity of the air is extremely low, then it shouldn't feel cold, right?
 
jostpuur said:
But they give the temperature in Fahrenheits and in Celsius. Those numbers must have some quantitative meaning.

Yes. Temperature means the average kinetic energy of the molecules.

jostpuur said:
This is a paradoxical statement, which IMO doesn't take into account the correct meaning of the terminology. If I understood this point correctly, this message should be said like this: "The average energy of the air molecules is high, but the temperature of the air as whole is low".

Well, I don't think it's paradoxical, and your proposed rewrite doesn't seem on the mark. I think you might be confusing temperature with the thermal transfer. If the average kinetic energy is high, then the temperature is high. But the mesophere's ability to warm objects in contact with it is low because there are so few particles. An object's temperature and it's ability to release heat into objects aren't the same thing.

When you put a room temperature beer in a cooler of ice, you always try to put the can deep in, under the water. Why? Because you have a sense that the cold water can cool down the can faster than the air, even though both are the same temperature within the cooler.
 
Cantab Morgan said:
When you put a room temperature beer in a cooler of ice, you always try to put the can deep in, under the water. Why? Because you have a sense that the cold water can cool down the can faster than the air, even though both are the same temperature within the cooler.

And even more so, I like to use ice water. Essentially the same temperature, but with complete surface contact.
 
Cantab Morgan said:
jostpuur said:
But they give the temperature in Fahrenheits and in Celsius. Those numbers must have some quantitative meaning.
Yes. Temperature means the average kinetic energy of the molecules.

You don't give the average kinetic energy in Fahrenheits or in Celsius. The temperature of a system means the reading that a temperature gauge will give when it is in contact with the system (and is in shadow from outside energy sources).
 
Guys, I understand what you mean. I mentioned something about heat transfer (I used word conductivity) in the update part of my post #3.

I'm thinking more: It could be that the temperature of the air is high, but a direct measurement of it becomes difficult because the time it takes for a reading of a gauge (or a temperature of a human skin) to settle is so large, that the black body radiation of the gauge itself (or of a skin), which will cool the gauge (or skin) down, messes it up.
 
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It's kind of like the question "which is heavier, a pound of feathers or a pound of rocks?"

Which will cook you faster, 1000 degree molten lead or 1000 degree hydrogen at 0.001 psia? :)
 
QuantumPion said:
It's kind of like the question "which is heavier, a pound of feathers or a pound of rocks?
Why the ROCKS of course! Rocks are like... rocks, well heavier man. I mean come on, feathers float!

ZING! Tally of flame posts from people with no sense of humour to follow.
 
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