The Beaufort scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Its full name is the Beaufort Wind Force Scale, although it is a measure of wind speed and not of force. The scale was devised in 1805 by Rear Admiral Sir Francis Beaufort, an Irish Royal Navy officer. In the early 19th century, naval officers made regular weather observations,
but there was no standard scale and could be very subjective – one man's "stiff breeze" might be another's "soft breeze". Sir Beaufort succeeded in standardizing the scale.
The initial Beaufort Number descriptions related wind conditions to effects on the sails of a frigate, then the main ship of the Royal Navy. In 1916, to accommodate the growth of steam power, the descriptions were changed to how the sea, not the sails,
behaved and extended to land observations.