How does oxygen change with altitude?
1 Answer
Oxygen doesn't change, but the partial pressure of oxygen changes with altitude.
Explanation:
The weight of the air above us causes the atmospheric pressure, which is roughly 760 mmHg at sea level.
Atmospheric pressure falls to about 380 mmHg at 5500 m and only 230 mmHg at 8900 m.
The proportion of oxygen is 21 % at all altitudes, so its partial pressure also decreases at higher altitudes.
(From a-deep-khinking.blogspot.com)
The decreased oxygen pressure reduces the driving force for gas exchange in the lungs.
The body makes a wide range of changes (acclimatization) to cope with the lack of oxygen at high altitude.
If you don’t acclimatize properly, you greatly increase your chance of developing altitude sickness.
