William Ferrel

Who was William Ferrel?

William Ferrel, an American meteorologist, developed theories which explained the mid-latitude atmospheric circulation cell in detail, and it is after him that the Ferrel cell is named. He was born in southern Pennsylvania. His family moved to what would become West Virginia in 1829. His formal elementary schooling was limited and he taught himself using science books well enough to become a school teacher. He attended Marshall College and despite financial difficulties, he was able to graduate from Bethany College's first graduating class in 1844. He would continue teaching in Missouri and Tennessee until 1858. At that point, he took up a full-time position on the staff of American Ephemeris and Nautical Almanac in Cambridge, Massachusetts. In 1882, Ferrel joined the U.S. Army Signal Service. He retired in 1887. He died in West Virginia in 1891.

Ferrel demonstrated that it is the tendency of rising warm air, as it rotates due to the Coriolis effect, to pull in air from more southerly, warmer regions and transport it poleward. It is this rotation which creates the complex curvatures in the frontal systems separating the cooler Arctic air to the north from the warmer continental tropical air to the south.