Hello steemit community. Wind speed, or wind flow velocity, is a fundamental atmospheric quantity.
Wind speed is caused by air moving from high pressure to low pressure, usually due to changes in temperature. Note that wind direction is usually almost parallel to isobars (and not perpendicular as one might expect), due to the rotation of the earth.
Wind speed affects weather forecasting, aircraft and maritime operations, construction projects, growth and metabolism rate of many plant species, and countless other implications.
Wind speed is now commonly measured with an anemometer but can also be classified using the older Beaufort scale which is based on people's observation of specifically defined wind effects.
An anemometer is commonly used to measure wind speed.
average wind speed.
Importance
For the wind industry it is very important to be able to describe the variation of wind speeds. Turbine designers need the information to optimize the design of their wind turbines, as well as to minimize generation costs. Investors need the information to estimate their income from electricity production.
The variation of the wind in a typical location is usually described using the so-called Weibull distribution, as shown in the drawing.
Probability and statistics
This particular location has an average wind speed of 7 meters per second, and the shape of the curve is determined by a shape parameter of 2.
The area under the curve is always exactly 1, since the probability that the wind blows at any of the speeds, including zero, must be 100 percent. Half of the blue area is to the left of the vertical black line at 6.6 meters per second. The 6.6 m/s are the median of the distribution. This means that half the time the wind will blow at less than 6.6m/s and the other half will blow at more than 6.6 m/s. If it is said that the average wind speed is 7 m/s, because the average wind speed is really the average of the observations of the wind speed that we will have in that location.
