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Why Do Some Volcanic Ash Clouds Travel Thousands of Kilometers Without Settling?

为什么某些火山灰云能飘行数千公里而不沉降?

Why Do Some Volcanic Ash Clouds Travel Thousands of Kilometers Without Settling?

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  1. Volcanic ash consists of tiny, jagged rock and glass particles blasted into the atmosphere during eruptions.

  2. When ejected above 10 km, ash enters the stratosphere where winds blow steadily and there’s little rain.

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