•Since the atmosphere in the polar regions is cold and the tropical atmosphere is warm, all pressure surfaces in the troposphere slope downward from the tropics to the polar regions.
•The pressure information on a constant altitude allow us to visualize where high- and low-pressure centers are located.
•The height information on a constant pressure surface convey the same information.
•The intensity of the pressure (or height) gradients allow us to infer the strength of the winds.