Tick Tack Toe

Duration: 00:33 minutes Upload Time: 2007-10-20 00:01:53 User: SSsiemianowice :::: Favorites :::: Top Videos of Day

Description: sky Jet streams are fast flowing, relatively narrow air currents found in the atmosphere at around 11 kilometers (36,000 ft) above the surface of the Earth. They form at the boundaries of adjacent air masses with significant differences in temperature, such as of the polar region and the warmer air to the south. The jet stream is mainly found in the tropopause, at the transition between the troposphere (where temperature decreases with height) and the stratosphere (where temperature increases with height)[1]. The major jet streams are westerly winds (flowing west to east) in both the Northern Hemisphere and the Southern Hemisphere, although in the summer, easterly jets can form in tropical regions. The path of the jet typically has a meandering shape, and these meanders themselves propagate east, at lower speeds than that of the actual wind within the flow. The theory of Rossby waves provides the accepted explanation for propagation of the meanders; Rossby waves propagate westward with respect to the flow in which they are embedded, but relative to the ground, they migrate eastward across the globe.