Why is it difficult to climb Mount Everest in terms of air pressure?

The difficulty of climbing Mount Everest is primarily linked to the reduced air pressure at high altitudes. At elevations like those found on Everest, air pressure decreases significantly compared to sea level. This reduction in atmospheric pressure leads to a drop in the partial pressure of oxygen. Since gas exchange in the body occurs via diffusion, the decreased partial pressure means that less oxygen is available to diffuse into the bloodstream from the alveoli in the lungs. Consequently, climbers struggle to obtain sufficient oxygen, leading to symptoms of altitude sickness and making the climb exceptionally challenging.

Higher altitudes indeed present the challenge of lower air pressure, which is a critical factor in understanding why climbing Everest is so strenuous, especially regarding the availability of oxygen necessary for sustaining physical performance.