The following changes are average changes, which means there might be exceptions more or less as we rise upward. But in general as elevation increases, on average:
Temperature decreases
Atm pressure decreases
Wind velocity increases
Gamma radiation increases
Overhead turns black
More and more stars are seen
Shape of the planet as a sphere becomes obvious
As your elevation increases the air temperature will drop on the average of 2 degrees C (3.5 degrees F) per 1000 feet.
In addition, oxygen levels decrease to the point at about 8000 ft MSL (above mean sea level) you will start to notice it. At above 12,500 feet MSL pilots are required to use supplement oxygen, and above 18,000 feet MSL all occupants of an aircraft must use oxygen. Lack of oxygen will lead to Hypoxia and unltimately death.
as you increase elevation the climate gets colder
There is increasingly less oxygen the higher the altitude.
Oxygen levels decrease to the point that nothing can survive without artificial life-support.
As you go higher, oxygen level gets lower.
it gets thinner and thinner
Nothing
The amount of dissolved oxygen decreases when water temperature increases. Warm water is unable to dissolve as much oxygen gas.
As a general rule in the atmosphere, the higher the elevation the lower the temperature. However, certain atmospheric conditions may produce an 'inversion', where temperature increases with elevation.
As the altitude or elevation increases the temperature decreases. The temperature drops about 6.5 degree Celsius for every I km increase.
it increases the fat content
As the water is poured into the glass, some oxygen dissolves in it. If the water doesn't move, the oxygen slowly diffuses out of it. If you were to pour in the water in a vacuum and then removed the vacuum and left the water stagnant, there would be no oxygen content decrease.
"air" and/or "oxygen"
If your elevation increases, not only does oxygen decrease but all gasses decrease. The greater distance you are from the earth's surface you are, the less air there is. When there is less air, there is less oxygen. No other gas increases to make up for the loss of oxygen.
The amount of dissolved oxygen decreases when water temperature increases. Warm water is unable to dissolve as much oxygen gas.
It is at sea level. The higher you climb from sea level, to reach the summit of Mount Everest (for example), the less oxygen is in the very thin air. This is why the majority of climbers of Mount Everest have to carry oxygen cylinders. Someone occasionally achieves the summit without oxygen tanks! Therefore, the higher the altitude, the thinner the oxygen in the air.
No. It is a negative correlation which means, as the elevation increases the air pressure decreases.
Venous reserve is available to maintain tissue oxygenation if either systemic oxygen demand increases or arterial content falls.
Temperature decreases as the elevation increases.
Air Pressure.
As a general rule in the atmosphere, the higher the elevation the lower the temperature. However, certain atmospheric conditions may produce an 'inversion', where temperature increases with elevation.
Yes. As elevation increases, combustion is more difficult to sustain, since each unit volume of gas contains less oxygen. Just like it is difficult for us to breathe at high altitude, so it is for a fire.
No. It changes negligably from the standard ~21% regardless of elevation. (at any elevation you can survive at anyway) :p The actual amount of available oxygen does change, due to a decrease in atmospheric density as elevation increases. For example: at 17,700ft (apparently a common Mt. Everest base camp) the air density is approximately 51% of the density at sea level. So you COULD express it as 51% of ~21%, which would be about 10.71%.
As silica content increases viscosity increases.