For decades, MayDay parades in Moscow have taken place under clear blue skies, aircraft having deposited dry ice, silver iodide and cement powder to disperse clouds.

几十年来，莫斯科的五月节游行都是在晴朗的蓝天下举行的，他们飞机上撒下干冰、碘化银和水泥粉来驱散云层。

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Clouds, overcast skies, and fog act as diffusion-something that scatters the light in many directions.

云层、阴沉的天空和大雾都会使光线发生漫射，漫射会将光线分散向各个方向。

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Clouds form along the upward cycle in the cylinders, where air is rising, and skies remain clear along the downward cycle, where air is falling.

云层形成在圆柱形旋转气流循环的上升段，即空气抬升阶段；而沿气流循环的下降段(空气下沉)的天空依然晴朗。

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The next year Griffith starred in the amiable military comedy "No Time for Sergeants, " and by 1960 "The Andy Griffith Show" was on network television and he was on his way to sweet, gentle fame, under blue skies and white clouds.

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But as the plane touched down, the last of the showers swept through, the clouds parted, and beautiful blue skies greeted Mrs.

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National Weather Service meteorologist Steve Anderson said there will be low clouds in the morning, partly cloudy skies in the afternoon and a mostly clear outlook for the evening.

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