Wind direction is reported by the direction from which it came from. For example, northern winds blow from north to south. Wind direction is usually reported in the direction of the wind or in degrees of azimuth. Wind direction is measured in degrees clockwise from the north and the wind coming from the north has a 0 degree wind direction; one from east 90 degrees; one from the south has a 180 degree wind direction. One from the west is 270 degrees or -90 degrees. In general, wind direction is sometimes expressed as -180 to 180, and sometimes 0 to 360.
Winds are named for the direction from which they come, followed by '-erly'. For example, the wind from the north is called 'north wind' (north-eerly).
Video Wind direction
Measurement techniques
Various instruments can be used to measure wind direction, such as windsock and wind vane. Both of these instruments work by moving to minimize air resistance. The way the weather vane shown by the prevailing wind shows the direction from which the wind blows. The opening of a larger windsock faces in the direction of the wind; Its tail, with smaller openings, points in the same direction as the wind blows.
Modern instruments used to measure wind speed and direction are called anemometers and wind propellers, respectively. This type of instrument is used by the wind energy industry, both for the assessment of wind resources and turbine control. Wind speed is measured by anemometer.
In situations where modern instruments are not available, the index finger can be used to test the wind direction. This is done by wetting your finger and pointing it up. The side of the finger that feels "cool" is (roughly) the direction from which the wind blows. The "cold" sensation is caused by the increased moisture evaporation rate on the fingers due to the airflow in the fingers, and consequently the "finger technique" measuring the wind direction does not work well at very humid or very hot. condition. The same principle is used to measure the dew point using a psychrometer sling (a instrument that is more accurate than a human finger).
Another primitive technique for measuring wind direction is to take a pinch of grass and drop it; the direction that the grass falls is the direction the wind is blowing. This latter technique is often used by golfers because it allows them to measure wind power.
Maps Wind direction
See also
- Yamartino method for calculating wind direction deviation
- The wind is clear
- Weather vane
- Wind power
- Air mass
References
Source of the article : Wikipedia
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