beaufort scale

scale for measuring wind force

After the British hydrographer Francis Beaufort (Navan, Meath County 1774-1857).

Beaufort was born in Ireland, the son of a clergyman of Huguenot descent who had a keen interest in geography and topography. Beaufort senior published one of the first detailed maps of Ireland in 1792.

Francis entered the service of the East India Company at the age of fifteen and the Royal Navy a year later. He was seriously wounded in a series of naval battles.

In 1805, the year of the Battle of Trafalgar, Beaufort designed a scale that enabled navigators, not least marines, to communicate about the strength of the wind.

He made a gradual division into thirteen wind strengths, based on the number of sails a British frigate could safely carry.

The mentions of 'wind force 7' or '5 on the Beaufort scale' in today's meteorological reports still go back to this British scientist, who was also active as an explorer and, in his 1817 book Caramania, described, among other things, the southern coasts of Lesser Asia and its ancient ruins.

Beaufort later became Sir Francis and rear admiral, and in 1828 official Royal Navy hydrographer. He passed away in 1857. Due to his British origin his name should strictly be pronounced 'boofrt'.

Sir George Simpson made the scale more comprehensible to steamship crews in 1905. He revised the descriptions and gave their equivalents in ordinary things, such as rising smoke, rustling leaves and moving weathervanes.

He reduced the original thirteen categories to twelve. Because seafaring nations here and there still had their own scales, Simpson was asked by the International Meteorological Committee in 1921 to develop a new standard.

In that modified scale he also included speeds in meters per second and kilometers per hour, so that the Beaufort scale could be further specified. He also established symbols that could be used on weather maps.

The result is a scale that starts with the number 0: no wind, smoke rises vertically, speed less than 1 km per hour. Number 6, for example, means : strong wind, thick branches move, telephone wires whistle, waves get bigger, speed 39 to 49 km per hour.

Finally, number 12: hurricane, the landscape is destroyed. Wind force 12 only occurs in the tropics, the speed is more than 117 km per hour. Although the Beaufort scale only goes up to 12, wind speeds of 140 to 150 km per hour are sometimes referred to as wind force 14 or 15.