Latitudes and Altitudes

Latitude is the angular distance from the equator, ranging from 0° at the equator to 90° at the poles, while altitude is simply how high a location sits above sea level. Both factors push temperature down as they increase, and both therefore produce very similar, predictable bands of vegetation. Moving from the equator toward the poles, temperature falls steadily from its maximum at the equator, and vegetation shifts through a recognisable sequence of zones. Climbing a mountain reproduces the exact same pattern over a much shorter horizontal distance: at high altitude, wind speed stays high while temperature and air pressure fall and humidity and light intensity rise, so vegetation again zones distinctly with elevation. The timber line (or tree line) marks the elevation above which trees stop growi …