We must have studied in the science chapters that the temperature and pressure change with height. On higher elevations, the air gets less dense and the temperature drops. The temperature on the surface of the earth is an effect of the radiation coming out of the earth. As higher altitudes are far away from the surface of the earth so these locations receive less radiation and the temperature remains cooler. The climate and vegetation of these regions also respond to these alternate conditions and feel different than on the surface.