Search results
Results from the WOW.Com Content Network
An anemometer is commonly used to measure wind speed. Global distribution of wind speed at 10m above ground averaged over the years 1981–2010 from the CHELSA-BIOCLIM+ data set [1] In meteorology, wind speed, or wind flow speed, is a fundamental atmospheric quantity caused by air moving from high to low pressure, usually due to changes in ...
The apparent wind on board (a boat) is often quoted as a speed measured by a masthead transducer containing an anemometer and wind vane that measures wind speed in knots and wind direction in degrees relative to the heading of the boat. Modern instrumentation can calculate the true wind velocity when the apparent wind and boat speed and ...
Wind speed increases with increasing height above the ground, starting from zero [dubious – discuss] [6] due to the no-slip condition. [8] Flow near the surface encounters obstacles that reduce the wind speed, and introduce random vertical and horizontal velocity components at right angles to the main direction of flow. [9]
The Yamartino method, introduced by Robert J. Yamartino in 1984, solves both problems [2] A further discussion of the Yamartino method, along with other methods of estimating the standard deviation of wind direction can be found in Farrugia & Micallef. It is possible to calculate the exact standard deviation in one pass.
Screenshot of the Global Wind Atlas website (version 2.2) The Global Wind Atlas is a web-based application developed to help policymakers and investors identify potential high-wind areas for wind power generation virtually anywhere in the world, and perform preliminary calculations. It provides free access to data on wind power density and wind ...
In a vector diagram such as the wind triangle, wind direction must be stated as the direction the wind is blowing to, or 180 degrees different from the convention. The ground vector represents the motion of the aircraft over the ground. It is described by ground track and ground speed. The ground vector is the resultant of algebraically adding ...
Consequently, a wind blowing from the north has a wind direction referred to as 0° (360°); a wind blowing from the east has a wind direction referred to as 90°, etc. Weather forecasts typically give the direction of the wind along with its speed, for example a "northerly wind at 15 km/h" is a wind blowing from the north at a speed of 15 km/h ...
Roughness length is a parameter of some vertical wind profile equations that model the horizontal mean wind speed near the ground. In the log wind profile, it is equivalent to the height at which the wind speed theoretically becomes zero in the absence of wind-slowing obstacles and under neutral conditions. In reality, the wind at this height ...