What is the effect of altitude on visibility during flight?

Visibility tends to increase with altitude due to a couple of key factors. As an aircraft climbs to higher altitudes, it often exits the lower layers of the atmosphere where pollution, fog, or other obstructions can significantly reduce visibility. These lower layers are generally characterized by greater moisture and particulates, which can scatter light and create haze.

Moreover, at higher altitudes, pilots may be above cloud cover or weather phenomena that could limit visibility at ground level. Consequently, being at a higher altitude often allows pilots a clearer view of the terrain and sky, with less atmospheric interference.

While it is essential to acknowledge that weather conditions can still influence visibility at high altitudes, the general trend is that visibility does increase as altitude rises, clearing out the obstructions that typically prevail in the lower atmosphere.