The six major controls of the climate are -pressure and wind system , distance from the sea, ocean currents, latitude, altitude, and relief features.
The amount of solar energy received varies w.r.t latitude, due to the curvature of the earth.
Hence, air temperature generally decreases from the equator towards the poles
Also, as one goes from the surface of the earth to higher altitudes , the atmosphere becomes less dense, pressure decreases, and temperature decreases .
As you increase in elevation, there is less air above you thus the pressure decreases.
As the pressure decreases, air molecules spread out further (i.e. air expands), and the temperature decreases.