As altitude increases, what happens to atmospheric pressure?

As altitude increases, atmospheric pressure decreases due to the decreasing weight of the air above a given point. The atmosphere is composed of layers of air, and as you ascend higher into the atmosphere, you encounter less air mass overhead. Since atmospheric pressure is the result of the weight of air pressing down from above, as you climb in altitude, there is less air above you exerting force, resulting in lower pressure. This relationship is a fundamental principle in atmospheric science and directly relates to how meteorological phenomena behave at different elevations.

The other options do not accurately describe this relationship: pressure does not increase with altitude because there is reduced weight of air; it does not remain constant as altitude changes; and while fluctuations can occur due to weather patterns, the overall trend with increasing altitude is a steady decrease in pressure.