What geographical factor leads to cooler temperatures at higher elevations?

The geographical factor that leads to cooler temperatures at higher elevations is elevation itself. As altitude increases, the atmosphere becomes thinner, and the air pressure decreases. This process affects temperature because the thinner air holds less heat. Consequently, temperature decreases with increasing elevation, a phenomenon known as the environmental lapse rate, which typically averages about 6.5 degrees Celsius for every kilometer ascended.

This principle can be observed in mountainous regions, where the peaks tend to be significantly colder than the valleys below. The influence of elevation is prominent in various climates and can lead to diverse ecological zones within relatively short distances vertically. While latitude, wind patterns, and coastal proximity can influence temperature and climate, they do not have the direct, consistent effect on temperature changes with height that elevation does.