Answer:
Beaufort scale
Explanation:
The Beaufort Wind Scale is titled after an admiral in Royal Navy, Sir Francis Beaufort. Of 1805, he created the scale to measure wind velocity by observing how sails shift in the wind.
Beaufort scale is broadly categories the wind in to 12 parts which he termed as Force 0 to Force 12.
force 0 termed as calm with speed less than 1 m/hr
force 1 termed as light air with speed 1- 3 mph
force 2 termed as slight breeze with speed 4-7 mph
force 3 termed as gentle breeze with speed 8-12 mph
force 4 termed as moderate breeze with speed 13-18 mph
force 5 termed as fresh breeze with speed 19-24 mph
force 6 termed as strong breeze with speed 25-31 mph
force 7 termed as moderate gale with speed 32-38 mph
force 8 termed as fresh gale with speed 39-46 mph
force 9 termed as strong gale with speed 47-54 mph
force 10 termed as whole gale with speed 55-63 mph
force 11 termed as storm gale with speed 64 -74 mph
force 12 termed as hurricane with speed 75 mph