Post by classvtony on Feb 14, 2010 21:42:21 GMT -8
This is kind a weak of post but you never know when that abstract will be replaced by the full article.
www.stormingmedia.us/87/8741/A874115.html
Abstract: The Sierra Nevada Range one of the most prominent and steepest mountain barriers in the United States and, not surprisingly, is a well-known location for a multitude of topographically forced atmospheric phenomena. As the prevailing westerly winds pass over the Sierra Nevada, gravity waves are frequently generated. Occasionally these mountain waves result in spectacular topographically forced phenomena such trapped lee waves, downslope windstorms, rotors, and attendant wave and rotor cloud structures, as shown in the examples Fig. 1. In situations such as those shown in Fig. 1, severe downslope winds near the surface, sometimes in excess of 50 m s(exp-1), decelerate rapidly in the lee and give way to a return flow back toward the mountain crest that is the lower branch of an intense horizontal circulation. These horizontal vortices, known as rotors, are common to the steep Tnrotors, are common to the steep eastern slopes of the Sierra Nevada, and particularly over the Owens Valley, where they are notorious for their intensity (e.g., Whelan 2000). Rotors have also been observed in a number of other mountainous regions, including the Rockies (Lester and Fingerhut 1974) and various locations in Europe (e.g., Queney et al. 1960). Rotors can be severe aeronautical hazards and have been cited as contributing to numerous aircraft encounters with severe turbulence and accidents, including occurrences involving modern commercial and military aircraft. Rotor circulations may also be important for the lifting and transport of aerosols and contaminants.
www.stormingmedia.us/87/8741/A874115.html
Abstract: The Sierra Nevada Range one of the most prominent and steepest mountain barriers in the United States and, not surprisingly, is a well-known location for a multitude of topographically forced atmospheric phenomena. As the prevailing westerly winds pass over the Sierra Nevada, gravity waves are frequently generated. Occasionally these mountain waves result in spectacular topographically forced phenomena such trapped lee waves, downslope windstorms, rotors, and attendant wave and rotor cloud structures, as shown in the examples Fig. 1. In situations such as those shown in Fig. 1, severe downslope winds near the surface, sometimes in excess of 50 m s(exp-1), decelerate rapidly in the lee and give way to a return flow back toward the mountain crest that is the lower branch of an intense horizontal circulation. These horizontal vortices, known as rotors, are common to the steep Tnrotors, are common to the steep eastern slopes of the Sierra Nevada, and particularly over the Owens Valley, where they are notorious for their intensity (e.g., Whelan 2000). Rotors have also been observed in a number of other mountainous regions, including the Rockies (Lester and Fingerhut 1974) and various locations in Europe (e.g., Queney et al. 1960). Rotors can be severe aeronautical hazards and have been cited as contributing to numerous aircraft encounters with severe turbulence and accidents, including occurrences involving modern commercial and military aircraft. Rotor circulations may also be important for the lifting and transport of aerosols and contaminants.
