Beaufort wind scale force name wind mph description 0 calm less than 1 air is still. He developed the scale in 1805 to help sailors estimate the winds via visual observations. Beaufort number force wind speed kmh mph kts ms description land conditions visual 0 wind motion visible in smoke. Force name wind speed effects beaufort scale in 1805, sir francis beaufort developed a system for estimating the speed of the wind. How to measure wind speed beaufort wind force scale the. Reference is made to table 21 bf number beaufort number as defined by the beaufort wind scale brake power, pb is the mcr brake power available in dp modebollard pull, i. Francis beaufort devised his scale of wind force in 1805, when serving aboard hms woolwich, and first mentioned it in his private log on january 1806, stating that he would, hereafter estimate the force of the wind according to the following scale. The most common way of measuring wind force is with the beaufort scale which defines a gale as wind from 50 kilometres per hour 14 ms to 102 kilometres per hour 28 ms. Beaufort scale beaufort wind scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Beaufort wind scale in miles per hour mph, knots and kilometers per hour kmh beaufort scale force wind in mph wind in knots wind in kmh description wave heightsvisible condition force 0 0 1 01 01 calm. By tradition, the magnitude of the wind is defined by the beaufort scale admiral beaufort, england, 1806. It is an empirical measure for describing wind speed based mainly on observed sea conditions. Beaufort scale from 0 to 12 geometric waves featuring adaptive hardware tessellation fast cpuside intersections with waves highquality pbrbased shading.
Even though the scale was created in the early 19th century it is still used today, especially at sea. Use the activity below to see what different levels of the scale look like. The beaufort scale has been around in one form or another for over 200 years. The scale ranges from 012, with 12 being for the strongest winds. Beaufort wind force scale matching activity here are the levels of the beaufort scale, which can be printed and cut up, to use as cards to match up. Beaufort scale of wind force mean probable wind average maximum speed in height height force descriptive term open sea criterion knots sea state in metres in metres 0 calm sea like a mirror beaufort wind scale 09262006 10.
Translate students observations into estimated miles per hour using the beaufort wind force scale. The beaufort wind force scale was developed in 1805 by british naval admiral francis beaufort. British educational youtuber trying to make sense of this complicated world we. The beaufort wind scale is divided into series of values, from zero for calm winds, up to twelve and above for hurricanes. It is based on observation rather than accurate measurement. Originally based on the effect of the wind on a fullrigged manofwar, in 1838 it became mandatory for log entries in all. Beaufort wind chart estimating winds speeds beaufort mph number range average terminology description 0 0 0 calm calm. A simple way to estimate wind speed approximate speed at 20 ft 6. The beaufort wind scale is based on observation of the sea, by way of a rough grouping from 1 to 12 bft. Beaufort developed the first versions of his wind force scale and weather notation coding, which he was. The beaufort scale is an empirical measure that relates wind speed to.
Kayaking inspired gifts sales help support this site. Wave heights in the scale are for conditions in the open ocean, not along the shore. The beaufort scale is an empirical measure that relates wind speed tae observed condeetions at sea or on laund. Sea surface like a mirror, but not necessarily flat. Crests of glassy appearance, not breaking wind felt. A system of estimating and reporting wind speed devised by british rearadmiral, sir francis beaufort 17741857 in 1805, based on observations of the effects of the wind.
Beaufort wind force scale specifications and equivalent speeds for use at sea force equivalent speed wave height description map us advisory specifications for use at sea. It is not the oldest, since rating the strength of wind by number andor assigning names to the ratings had been done for some time. Beaufort s diary from 1806 showing his original scale. The observed wave pattern in deep sea is related to the generating wind force. The beaufort wind force scale was developed in 1805 by british naval admiral francis.
Dnvglst0111 assessment of station keeping capability of. Noaa national weather service national centers for environmental prediction weather prediction center 5830 university research court college park, maryland 20740 weather prediction center web team. One of the first scales to estimate wind speeds and the effects was created by britains. In 1806 francis beaufort later admiral and sir wrote out a numerical scale in his log. The beaufort scale is a scale for measuring wind speeds.
Beaufort wind scale in miles per hour mph, knots and. The beaufort wind scale, which is used to describe the force of the wind, was invented by admiral beaufort in 1805. With some experience with the use of the scale the wind force can be estimated with reasonable accuracy. Beaufort arranged the numbers 0 to 12 to indicate the strength of the wind from calm force 0 to hurricane force 12. Specifications and equivalent speeds for use at sea. The beaufort scale is still used today to estimate wind strengths. His system to estimate and report wind speeds was based on the amount of canvas sail that a fullrigged frigate a large military sailing ship could carry. It is the most widely used system to measure wind speed today. Below is a table showing the beaufort scale with speeds in knots, miles per hour and kilometers per hour. Lift up flap beaufort scale activity teaching resources. The scale was developed in 1805 by francis beaufort, an officer of the royal navy and first officially used by hms beagle there are twelve levels, plus 0 for no wind. Beaufort scale, in full beaufort wind force scale, scale devised in 1805 by commander later admiral and knight commander of the bath francis beaufort of the british navy for observing and classifying wind force at sea. F1 tornadoes on the fujita scale and t2 torro scale also begin roughly at the end of level 12 of the beaufort scale, but are independent scales although the torro scale wind values are based on the 32 power law relating wind velocity to beaufort force.
The beaufort scale has become the standard method of judging wind force. Beaufort wind force scale number wind speed description wave height sea conditions land conditions mph kts m ft 0 wind motion visible in smoke. The beaufort scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Both mariners and landlubbers all around the world use the scale to estimate wind speed in a standardized way. In addition to recording cloud conditions, estimate wind speed by observing the effects of wind on tree leaves, flags, litter, smoke, hair, and clothes. Problem solving beaufort scale the beaufort scale is normally used at sea to describe how windy it is. Investigating clouds, a lesson plan from the national science digital library that uses the beaufort scale. The beaufort scale was developed by an irish sailor named francis beaufort. The scale was developed in 1805 by sir francis beaufort. The scale was developed in 1805 by sir francis beaufort there are twelve levels, plus 0 for no wind. At each point he gave the wind a number, a name and a description of its effects.