The seasonal reversal of wind field from the upper troposphere to the stratosphere is as pronounced as in the middle and lower troposphere.

东亚对流层中上部和平流层中下部风场的季节变化，与对流层中下部一样显著。

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While the aircraft has flown before, this was the first flight for it after being loaded up with eleven different scientific instruments, which will be used to examine trace gases, aerosols, and dynamics of the upper troposphere and lower stratosphere.

ENGADGET: NASA's unmanned Global Hawk completes key test flight