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A large body of air that has consistent properties throughout , such as temperature and moisture content , at a given altitude .
A colorful display of light in the ionosphere , produced when charge particles form the sun are attracted to Earth's magnetic poles .
A dense , visible mass of tiny water droplets or ice crystals that are suspended in the atmosphere .
Puffy white clouds , usually with flat balloons , that look like piles of cotton balls .
A day that marks the beginning of spring or autumn ; a day on which the length of daylight and darkness are approximately equal .
A large tropical cyclone with winds of at least 119 kilometer per hour (74 miles per hour) .
A region of charge particle , or ions , in Earth's atmosphere that overlaps the lower thermosphere .
The ratio of the amount of water vapor in the air to the maximum amount of water vapor that air can contain at that temperature .
The day that marks the start of summer or winter , the day when the sun is directly overhead at latitude 23.5 degrees north or latitude 23.5 degrees south .
A front that occurs when two air masses have formed a boundary , but neither is moving .
A small , But intense windstorm that takes the form of a rotating column of air that touches the ground .
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