Beaufort scale

Beaufort scale a scale of wind velocity devised (c.1805) by Admiral Sir Francis Beaufort of the British navy. An adaptation of Beaufort's scale is used by the U.S. National Weather Service; it employs a scale from 0 to 12, representing calm, light air, light breeze, gentle breeze, moderate breeze, fresh breeze, strong breeze, moderate gale, fresh gale, strong gale, whole gale, storm, hurricane. Zero (calm) is a wind velocity of less than 1 mi (1.6 km) per hr, and 12 (hurricane) represents a velocity of more than 74 mi (119 km) per hr.

Beaufort's original scale was later correlated to wind speed in two different ways. The U.S. and British scale is for winds measured at a 36-ft elevation, while the international scale requires only a 20-ft elevation. The Beaufort scale is the oldest method of judging wind force. Separate scales for tornadoes and hurricanes did not come until the 1970s. The Fujita scale for tornadoes was proposed in 1971 by Tetsuya (Ted) Fujita; in 2007 the Enhanced Fujita scale, incorporating improved knowledge of wind destruction, as was adopted. Soon after the development of the Fujita scale the Saffir-Simpson scale for hurricanes was formulated by Herbert Saffir and Robert Simpson.

Bibliography: See A. Shaw, Beaufort Wind Scale (1995).

Beau·fort scale / ˈbōfərt/ a scale of wind speed based on a visual estimation of the wind's effects, ranging from force 0 (less than 1 knot or 1 kph, “calm”) to force 12 (64 knots or 118 kph and above, “hurricane”).

Beaufort Scale, the internationally recognized scale for wind and weather which was drawn up by Sir Francis Beaufort (1774–1857), a British rear admiral who served as Hydrographer of the Navy from 1829 to 1855. See illus. opposite.

Beaufort ScaleUsed to indicate the force of the wind.

Bibliography

Courtney, N. , Gale Force 10: The Life and Legacy of Admiral Beaufort (2002).