WIND

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Last Modified: 20051101.12:10 by RTSmith

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Wind

Wind is air in motion.

In weather reports or forecasts, wind typically refers only to horizontal motions of air relative to the surface of the earth. However, in everyday usage, the term wind might also be used when referring to instances of rising or sinking air (e.g., updrafts, thermals, downdrafts).

There are four characteristics of wind that can be observed, described, or measured: direction, speed, character (e.g., gusts and squalls), and shifts. Surface winds are measured by wind vanes and anemometers, while upper-level winds are detected through pilot balloons, rawin, or aircraft reports. A wind sock can also be used to estimate wind speed and direction. For additional information about measuring wind, you might also wish to visit the following web sites: http://www.nssl.noaa.gov/~cortinas/1014/l23_1.html and http://www.usatoday.com/weather/wanemom.htm

Wind can occur on various scales.

Recurring regional winds often have special names.

Wind can have numerous effects.

Wind speed in a hurricane can reach 300 kilometers (~190 miles) per hour.
The highest recorded speed for a gust of (non-tornado) wind -- 371 kilometers (231 miles) per hour -- occurred on Mount Washington in New Hampshire on April 12, 1934. (Preliminary reports when Typhoon Paka hit the island of Guam on December 16, 1997, indicated a peak gust of 236 miles per hour. However, the National Climate Extremes Committee issued a statement on March 11, 1998, indicating that the hot-wire anemometer data recorded during the typhoon were unreliable.)
Adélie Land, on the coast of Antarctica, sustains wind speeds that average 80 kilometers (50 miles) per hour.
Within a tornado, it is believed that the wind can reach speeds of 650 kilometers (>400 miles) per hour. On May 13, 1999, scientists using a truck-mounted Doppler radar system measured a wind speed of 509 kilometers (318 miles) per hour inside a tornado that struck Oklahoma City. (See http://www.trv-psitech.com/tornado3.htm for more details.) To my knowledge, this is the fastest wind speed ever recorded on Earth thus far.

For additional information about wind and what causes it, try visiting one or more of the following links:

USA Today Weather: The What and Why of Wind
Kids as Global Scientists: Wind Explanation
Earth and Sky Transcript (March 3, 1997): What Causes Wind?
Wind: Our Fierce Friend, a curriculum unit by The Franklin Institute Science Museum
Wind Structure and Characteristics provides an extensive article on the nature of wind and related weather phenomena
The Danish Wind Turbine Manufacturers Association's Guided Tour on Wind Energy provides extensive information (and some interesting graphic displays) dealing with wind, wind energy, and wind energy resources

This page was originally created by R. Timothy Smith when he was an overworked, underpaid Academic Specialist with the Department of Teacher Education in the College of Education at Michigan State University (1993-2001).