Hint:Anemometers are wind measurement devices that can register wind speed, direction, and the frequency of gusts. The roughness of the terrain, as well as the prevalence of buildings, trees, and other objects in the vicinity, influence wind strength, which rises with height above the earth's surface.
Complete answer: Wind speed, also known as wind flow speed in meteorology, is a basic atmospheric quantity caused by air travelling from high to low pressure, typically due to temperature variations.An anemometer is now widely used to measure wind speed. Weather forecasts, aviation and marine activity, building programmes, the development and metabolism rate of many plant species, and a slew of other things are all affected by wind speed. Due to Earth's rotation, wind direction is almost always almost parallel to isobars (rather than perpendicular, as one would expect).
The best location for wind calculation is on flat ground with uniform roughness and no significant barriers within 300 metres of the antenna. In fact, only a few sites in the observing network precisely satisfy this criterion for all event wind paths, but the majority are relatively reflective of an open location.
The knot (nautical mile per hour = 0.51 m sec-1 = 1.15 mph) is the standard measurement of wind speed. The wind direction is registered from where the wind is blowing and is determined relative to true north (not magnetic north). A knot is a unit of wind speed that is commonly used in meteorology, as well as in sea and air navigation. One knot is approximately 1.15 statute miles in math. The height above ground at which wind speed data is measured is known as the anemometer height.
Note:A cup anemometer, which consists of three or four conical or hemispherical cups placed symmetrically along a vertical spindle, is used to measure wind speed. The spindle rotates due to the breeze flowing through the cups. The geometry of the cups in regular instruments is such that the rate of rotation is equal to the wind speed to a fairly good approximation. Anemometers are adjusted in a wind tunnel every five years to detect any deviations from the manufacturer's established relationship between spindle rotation and wind speed. The determined wind speed is subjected to calibration corrections.