Isobars

 Isobars

Atmospheric Pressure of The United States

http://www.solcomhouse.com/windpower.htm

Isobar maps are very similar to contour line but instead these lines show areas of equal atmospheric pressure. The closer that these lines are together we will experience a more rapid change in pressure. From the above map of the North America we can observe the closeness of the contour lines in the eastern half of the United States.