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Mesovortices are small scale rotational features found in convective storms, such as those found in bow echos, supercell thunderstorms, and the eyewall of tropical cyclones. They range in size from tens of miles in diameter to a mile,〔(【引用サイトリンク】title=Facts About Derechos )〕 and can be immensely intense. ==Eyewall mesovortices== ''Eyewall mesovortices'' are small scale rotational features found in the eyewalls of intense tropical cyclones. They are similar, in principle, to small "suction vortices" often observed in multiple-vortex tornadoes. In these vortices, wind speed can be up to 10% higher than in the rest of the eyewall. Eyewall mesovortices are most common during periods of intensification in tropical cyclones. Eyewall mesovortices often exhibit unusual behavior in tropical cyclones. They usually rotate around the low pressure center, but sometimes they remain stationary. Eyewall mesovortices have even been documented to cross the eye of a storm. These phenomena have been documented observationally,〔 experimentally, and theoretically. Eyewall mesovortices are a significant factor in the formation of tornadoes after tropical cyclone landfall. Mesovortices can spawn rotation in individual thunderstorms (a mesocyclone), which leads to tornadic activity. At landfall, friction is generated between the circulation of the tropical cyclone and land. This can allow the mesovortices to descend to the surface, causing large outbreaks of tornadoes. Hurricane hunter, NOAA42, accidentally flew through an eyewall mesovortex measuring 320 km/h and experienced crippling G-forces of +5.8Gs and -3.7Gs during observations for Hurricane Hugo on 15 September 1989. The winds ripped-off the propeller de-icing boot and pushed the flight down to a perilous 1000 ft above sea level. The ruggedized Lockheed WP-3D Orion was only designed for a maximum of +3.5Gs and -1G. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mesovortices」の詳細全文を読む スポンサード リンク
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