William Ferrel

William Ferrel (1817 - 1891), 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.

Ferrel demonstrated that it is the tendency of rising warm air, as it rotates under the effect of the Coriolis force, 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.