Final answer:
Weather primarily occurs in the Earth's troposphere. This is the first layer of the Earth's atmosphere and contains approximately 80% of total atmospheric mass. Weather events such as wind and precipitation arise due to temperature and air density changes within this layer.
Step-by-step explanation:
Weather primarily occurs in the Earth's troposphere. The Earth's atmosphere consists of five major layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere. However, it is specifically in the troposphere that the majority of weather events originate. This is the layer closest to the Earth's surface, extending up to approximately 12 km above sea level. The troposphere contains about 80% of the Earth's atmosphere by mass.
Weather is the name we give to the circulation of the atmosphere, powered energetically primarily by sunlight that heats the surface of the Earth. The troposphere is the layer in which this atmospheric circulation is most prevalent due to the fact that temperature and air density both decrease as you ascend higher into this layer, which causes changes in pressure and initiates weather events such as wind and precipitation.
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