Search results
Results from the WOW.Com Content Network
The fastest wind speed not related to tornadoes ever recorded was during the passage of Tropical Cyclone Olivia on 10 April 1996: an automatic weather station on Barrow Island, Australia, registered a maximum wind gust of 113.3 m/s (408 km/h; 253 mph; 220.2 kn; 372 ft/s) [6] [7] The wind gust was evaluated by the WMO Evaluation Panel, who found ...
The radius of curvature of the sound path is inversely proportional to the velocity gradient. [50] A wind speed gradient of 4 (m/s)/km can produce refraction equal to a typical temperature lapse rate of 7.5 °C/km. [51] Higher values of wind gradient will refract sound downward toward the surface in the downwind direction, [52] eliminating the ...
In this equation, represents the wind velocity measured at height , and is the von Kármán constant, roughly valued at 0.4. This relationship is indicative of the logarithmic wind profile, which describes the variation of wind speed with altitude, influenced by surface texture and atmospheric conditions.
The time that a sonic pulse takes to travel from one transducer to its pair is inversely proportionate to the speed of sound in air plus the wind velocity in the same direction: = (+) where is the time of flight, is the distance between transducers, is the speed of sound in air and is the wind velocity. In other words, the faster the wind is ...
The power law is often used in wind power assessments [4] [5] where wind speeds at the height of a turbine ( 50 metres) must be estimated from near surface wind observations (~10 metres), or where wind speed data at various heights must be adjusted to a standard height [6] prior to use.
13.9–17.1 m/s 13–19 ft 4–5.5 m Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind; spindrift begins to be seen Whole trees in motion; inconvenience felt when walking against the wind 8 Gale, fresh gale 34–40 knots 39–46 mph 62–74 km/h 17.2–20.7 m/s 18–25 ft 5.5–7.5 m
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The log wind profile is generally considered to be a more reliable estimator of mean wind speed than the wind profile power law in the lowest 10–20 m of the planetary boundary layer. Between 20 m and 100 m both methods can produce reasonable predictions of mean wind speed in neutral atmospheric conditions.